Introduction to GIS Training manual

GIS Training Manual ArcGIS 10.5 Prepared By: Binyam Tesfaw Hailu, PhD : a member of CHIESA Project Assistant Professor of Remote Sensing and GIS, P.O.Box:1176 Tel: +251-111-239462 Mobile: +251-921-337833 e-mail: binyam.tesfaw@aau.edu.et, binyamtesf@yahoo.com

The Adaptation for Ecosystem Resilience in Africa (AFERIA) is a two-year project to disseminate and communicate research results, insights and interactions of climate change and food security developed from a previous research and development project (CHIESA-Climate Change Impacts on Ecosystem Services and Food Security in Eastern Africa).

Funded by:

Coordinated By:

GIS Practical Training, ArcGIS 10.5

Table of Contents 1

What is GIS? (Day 1) ....................................................................................................... 4

1.1 Definition ........................................................................................................................ 4 1.2 Why GIS? ........................................................................................................................ 4 1.3 GIS Components ............................................................................................................. 5 1.4 GIS Applications ............................................................................................................. 5 1.5 Data sources for GIS ....................................................................................................... 6 1.6 GIS Data: Vector and Raster Data .................................................................................. 6 1.6.1 Vector based GIS ..................................................................................................... 6 1.6.2 Raster based GIS ...................................................................................................... 7 1.7 Coordinate systems ......................................................................................................... 7 1.7.1 Introduction .............................................................................................................. 7 1.7.2 Geographic Coordinate System (GCS) .................................................................. 10 1.7.3 Map Projections ..................................................................................................... 11 1.7.4 The Universel Transverse Mercator (UTM) system: ............................................. 14 2 Exploring ArcCatalog, ArcMap 10, and ArcToolbox ................................................... 15 2.1 Exploring ArcCatalog (Day-2) ...................................................................................... 15 2.1.1 Viewing data in ArcCatalog................................................................................... 15 2.1.2 Connecting to your data ......................................................................................... 17 2.1.3 Managing your data in ArcCatalog ........................................................................ 18 2.2 Exploring ArcMap 10 (Day-2) ...................................................................................... 18 2.2.1 Displaying and viewing Spatial Datasets in ArcMap 10 ....................................... 19 2.2.2 Exploring data in ArcMap 10 ................................................................................ 20 2.2.3 Referencing data on a map ..................................................................................... 22 2.2.4 Changing how features are drawn.......................................................................... 22 2.2.5 Adding labels to a map .......................................................................................... 23 2.2.6 Displaying Attribute tables behind the maps ......................................................... 23 2.2.7 Querying data in ArcMap 10 ................................................................................. 24 2.2.8 Advanced Query (Day 3) ....................................................................................... 26 3 Cartographic applications of ArcGIS (day 3) ................................................................ 27 3.1 Working with Symbology in ArcMap 10 ...................................................................... 27 3.1.1 Classifying data ...................................................................................................... 27 3.2 Symbolizing data in Arc map ........................................................................................ 29 3.2.1 Symbolizing point data .......................................................................................... 29 3.2.2 Symbolizing linear data ......................................................................................... 29 3.2.3 Symbolizing areal data ........................................................................................... 30 3.2.4 Create custom symbols .......................................................................................... 30 4 Georeferencing Scanned Data (Day 4) .......................................................................... 31 4.1 How to Georeference a raster dataset ............................................................................ 31 4.1.1 Georeferencing a raster dataset .............................................................................. 31 4.1.2 Entering specific x, y map coordinates .................................................................. 33 5 Editing and data compilation ......................................................................................... 33 5.1 Methods of collecting data ............................................................................................ 34 5.1.1 Digitizing data ........................................................................................................ 34 5.1.2 Collecting data in the field ..................................................................................... 34 5.2 Workflow for creating and editing features .................................................................. 35 2 © Binyam Tesfaw Hailu, PhD AAU 2017

GIS Practical Training, ArcGIS 10.5 5.2.1 5.2.2 5.2.3 5.2.4 5.2.5 5.2.6

Choosing the workspace and starting an edit session ............................................ 36 Setting the target layer ........................................................................................... 37 Choosing an edit task ............................................................................................. 37 Choosing a tool and creating an edit sketch........................................................... 37 Examples of edit tasks and sketches used together ................................................ 39 Editing existing features with sketches .................................................................. 39

5.3 Adding attribute information................................................................................. 39 5.3.1 Methods of editing attributes ................................................................................. 40 5.4 The snapping environment ............................................................................................ 41 5.5 Editing shared geometry................................................................................................ 41 5.5.1 Completing polygons using existing polygon geometry ....................................... 42 5.5.2 About splitting polygon features (Cut Polygon Features) ..................................... 43 5.5.3 How to split polygon features ................................................................................ 43 Splitting polygons by drawing a sketch ............................................................................... 43 6 Presenting data (Day 5) .................................................................................................. 43 6.1 Preparing map layout .................................................................................................... 43 6.1.1 Converting labels to map document annotation..................................................... 44 6.1.2 Switching to Layout View .................................................................................. 44 6.1.3 Setting the page size and printer properties ........................................................... 46 6.1.4 Resizing and moving data frame............................................................................ 46 6.2 Inserting Legend, Scale bar, Title… ............................................................................. 47 6.2.1 Adding a scalebar ................................................................................................... 47 6.2.2 Adding a North arrow ............................................................................................ 47 6.2.3 Adding a legend ..................................................................................................... 47 6.2.4 Adding a title.......................................................................................................... 48 6.3 Inserting Grids and Graticules....................................................................................... 48 6.4 Printing a map ............................................................................................................... 50 6.4.1 Saving a map as a map template ......................................................................... 50 6.4.2 Exporting your map to other file formats .............................................................. 50 6.5 Work with map templates ............................................................................................. 50 6.5.1 Opening a temple when you first start ArcMap 10 ............................................. 50 6.5.2 Opening a new template while in ArcMap 10 ....................................................... 50

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1 What is GIS? (Day 1) 1.1 Definition Like the field of geography, the term Geographic Information System (GIS) is hard to define. It represents the integration of many subject areas. Accordingly there us no absolutely agreed upon definition of a GIS (deMers, 1997). A broadly accepted definition of GIS is the one provided by the National Center of Geographic Information and Analysis: a GIS is a system of hardware, software and procedures to facilitate the management, manipulation, analysis, modeling, representation and display of georeferenced data to solve complex problems regarding planning and management of resources (NCGIA, 1990) Geographic information systems have emerged in the last decade as an essential tool for urban and resource planning and management. Their capacity to store, retrieve, analyze, model and map large areas with huge volumes of spatial data has led to an extraordinary proliferation of applications.

Geographic information systems are now used for land use planning, utilities management, ecosystems modeling, landscape assessment and planning, transportation and infrastructure planning, market analysis, visual impact analysis, facilities management, tax assessment, real estate analysis and many other applications.

Functions of GIS include: data entry, data display, data management, information retrieval and analysis.

1.2 Why GIS? It is important for: Mapping locations: GIS can be used to map locations. GIS allows the creation of maps through automated mapping, data capture, and surveying analysis tools.

Mapping quantities: People map quantities, like where the most and least are, to find places that meet their criteria and take action, or to see the relationships between places. This gives an additional level of information beyond simply mapping the locations of features.

Mapping densities: While you can see concentrations by simply mapping the locations of features, in areas with many features it may be difficult to see which areas have a higher concentration than others. A density map lets you measure the number of features using a uniform areal unit, such as acres or square miles, so you can clearly see the distribution.

Finding distances: GIS can be used to find out what's occurring within a set distance of a feature.

Mapping and monitoring change: GIS can be used to map the change in an area to anticipate future conditions, decide on a course of action, or to evaluate the results of an action or policy.

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1.3 GIS Components GIS is comprised of hardware, software, data, humans, and a set of organizational protocols.

These components must be well integrated for effective use of GIS, and the development and integration of these components is an iterative, ongoing process. The selection and purchase of hardware and software is often the easiest and quickest step in the development of a GIS. Data collection and organization, personnel development, and the establishment of protocols for GIS use are often more difficult and time-consuming endeavors.

1.4 GIS Applications

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1.5 Data sources for GIS Data for GIS applications includes:  Digitized and scanned data: Analog maps  Databases: Reports  GPS field sampling of attributes  Remote sensing and aerial photography

1.6 GIS Data: Vector and Raster Data 1.6.1 Vector based GIS General definitions Vector is a data structure, used to store spatial data. Vector data is comprised of lines or arcs, defined by beginning and end points, which meet at nodes.

Vector representation of data In the vector based model, geospatial data is represented in the form of co-ordinates. In vector data, the basic units of spatial information are points, lines (arcs) and polygons. Each of these units is composed simply as a series of one or more co-ordinate points, for example, a line is a collection of related points, and a polygon is a collection of related lines.

Co-ordinate Pairs of numbers expressing horizontal distances along orthogonal axes, or triplets of numbers measuring horizontal and vertical distances, or n-numbers along n-axes expressing a precise location in n-dimensional space. Co-ordinates generally represent locations on the earth's surface relative to other locations.

Point A zero-dimensional abstraction of an object represented by a single X, Y co-ordinate. © Binyam Tesfaw Hailu, PhD AAU 2017

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GIS Practical Training, ArcGIS 10.5 Line A set of ordered co-ordinates that represent the shape of geographic features too narrow to be displayed as an area at the given scale (contours, street centerlines, or streams), or linear features with no area (county boundary lines). A line is synonymous with an arc.

Arc An ARC/INFO term that is used synonymously with line.

Polygon A feature used to represent areas. A polygon is defined by the lines that make up its boundary and a point inside its boundary for identification. Polygons have attributes that describe the geographic feature they represent.

1.6.2 Raster based GIS Raster representation of data Raster is a method for the storage, processing and display of spatial data. Each area is divided into rows and columns, which form a regular grid structure. Each cell must be rectangular in shape, but not necessarily square. Each cell within this matrix contains location co-ordinates as well as an attribute value. The spatial location of each cell is implicitly contained within the ordering of the matrix, unlike a vector structure, which stores topology explicitly. Areas containing the same attribute value are recognized as such, however, raster structures cannot identify the boundaries of such areas as polygons.

Raster data is an abstraction of the real world where spatial data is expressed as a matrix of cells or pixels, with spatial position implicit in the ordering of the pixels. With the raster data model, spatial data is not continuous but divided into discrete units. This makes raster data particularly suitable for certain types of spatial operation, for example overlays or area calculations.

Raster structures may lead to increased storage in certain situations, since they store each cell in the matrix regardless of whether it is a feature or simply 'empty' space.

Grid size and resolution A pixel is the contraction of the words picture element. Commonly used in remote sensing to describe each unit in an image. In raster GIS the pixel equivalent is usually referred to as a cell element or grid cell. Pixel/cell refers to the smallest unit of information available in an image or raster map. This is the smallest element of a display device that can be independently assigned attributes such as color.

1.7 Coordinate systems 1.7.1 Introduction Coordinate: A set of numbers that designate location in a given reference system, such as x,y in a planar coordinate system or x,y,z in a three-dimensional coordinate system. Coordinate pairs represent a location on the earth's surface relative to other locations. © Binyam Tesfaw Hailu, PhD AAU 2017

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GIS Practical Training, ArcGIS 10.5 A Coordinate System is a reference system used to measure horizontal and vertical distances on a planimetric map. A coordinate system is usually defined by a map projection, a spheroid of reference, a datum, one or more standard parallels, a central meridian, and possible shifts in the x- and y-directions to locate x, y positions of point, line, and area features. There are two major types of coordinate systems in use today, namely geographic and projected coordinate systems, which are covered in the following sections.

Spheroid A sphere is based on a circle, while a spheroid (or ellipsoid) is based on an ellipse. The shape of an ellipse is defined by two radii. The longer radius is called the semi-major axis, and the shorter radius is called the semi-minor axis. The earth’s shape can be represented by an ellipsoid of rotation or a Spheroid that is slightly flattened in the poles (Fig. 8.1). A spheroid is defined by the semi-major axis, a, and the semi-minor axis, b, or by a and the flattening. The flattening is the difference in length between the two axes expressed as a fraction or a decimal. The flattening, f, is: f = (a - b) / a ........................................................................8.1 The flattening ranges from zero to one. A flattening value of zero means the two axes are equal, resulting in a sphere. The flattening of the earth is approximately 0.003353. This value varies for different measurements of a and b made at different times. Table 8.1 shows some of the most commonly used spheroid with their parameters.

Although the earth is best represented by a spheroid, it is sometimes treated as a sphere to make mathematical calculations easier. The assumption that the earth is a sphere is possible for smallscale maps (smaller than 1:5,000,000). At this scale, the difference between a sphere and a spheroid is not detectable on a map. However, to maintain accuracy for larger-scale maps (scales of 1:1,000,000 or larger), a spheroid is necessary to represent the shape of the earth.

Between those scales, choosing to use a sphere or spheroid will depend on the map’s purpose and the accuracy of the data.

Figure 8.1 Simplified representation of the Earth

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Date

Ellipticity, f

1984 1972 1940

Name of ellipsoid Length of semi-axes (m) Major (a) Minor (b) WGS84 6378137 6356752.3 WGS72 6378135 6356750.5 Krasovsky 6378245 6356863

1924 1880 1866 1841

International Clarke 1880 Clarke 1866 Bessel

1/297 1/293.46 1/294.98 1/299.15

6378388 6378249.1 6378206.4 6377397.2

6356911.9 6356514.9 6356583.8 6356079

1/298.257 1/298.26 1/298.3

Mainly used in World World Eastern Europe World Africa N. America Asia

Table 8.1 Some official ellipsoids in use throughout the world Datum While a spheroid approximates the shape of the earth, a datum defines the position of the spheroid relative to the center of the earth. A datum provides a frame of reference for measuring locations on the surface of the earth. A local datum aligns its spheroid to closely fit the earth’s surface in a particular area (Fig. 8.2). A point on the surface of the spheroid is matched to a particular position on the surface of the earth. This point is known as the origin point of the datum. The coordinates of the origin point are fixed, and all other points are calculated from it.

Whenever we change the datum, the coordinate values of the data will change.

In the last 25 years, satellite data has provided geodesists with new measurements to define the best earth-fitting spheroid, which relates coordinates to the earth’s center of mass. An earthcentered, or geocentric, datum uses the earth’s center of mass as the origin. The most recently developed and widely used datum is WGS 1984. It serves as the framework for locational measurement worldwide. NAD 1927 and the European Datum of 1950 (ED 1950) are local datums. NAD 1927 is designed to fit North America reasonably well, while ED 1950 was created for use in Europe. Adindan is the most frequently used datum in Eastern Africa in general and in Ethiopia in particular. Because a local datum aligns its spheroid so closely to a particular area on the earth’s surface, it’s not suitable for use outside the area for which it was designed.

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Figure 8.2 Earth-centred versus local-datum based on a spheroid

1.7.2 Geographic Coordinate System (GCS) GCS uses a three dimensional spherical surface to define locations on the earth. A GCS is often incorrectly called a datum, but a datum is only one part of a GCS. A GCS includes an angular unit of measure, a prime meridian, and a datum (based on a spheroid). A point is referenced by its longitude and latitude values. Longitude and latitude are angles measured from the earth’s center to a point on the earth’s surface (Figure 8.4). The angles often are measured in degrees (or in grads). A point on the globe is represented by triple coordinates (,,r) on a spherical coordinate system. Assuming that the earth is perfectly spherical, the radius, r becomes constant for any point on the globe. Therefore a point can be represented by the two angular coordinates (,). This is the basis for the geographic (latitude-longitude) coordinate system of Figure 8.4.

In the spherical system, ‘horizontal lines’, or east–west lines, are lines of equal latitude, or parallels. ‘Vertical lines’, or north–south lines, are lines of equal longitude, or meridians. These lines encompass the globe and form a girded network called a graticule (Fig. 8.4).

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GIS Practical Training, ArcGIS 10.5 Greenwich/Prime Meridian Meridians (Lines of longitude)

Parallels (Lines of latitude) Equator

Figure 8.4 Coordinate reference on a sphere – GCS

1.7.3

Map Projections

Spherical coordinate systems such as GCS are not convenient for most GIS applications.

Whether we treat the earth as a sphere or a spheroid, we must transform its three-dimensional surface to create a flat map sheet. This mathematical transformation is commonly referred to as a map projection. One easy way to understand how map projections alter spatial properties is to visualize shining a light through the earth onto a surface, called the projection surface. Imagine the earth’s surface is clear with the graticule drawn on it. Wrap a piece of paper around the earth. A light at the center of the earth will cast the shadows of the graticule onto the piece of paper. You can now unwrap the paper and lay it flat. The shape of the graticule on the flat paper is very different than on the earth. The map projection has distorted the graticule.

A map projection uses mathematical formulas to relate spherical coordinates on the globe to flat, planar coordinates. x= f1() y=f2() Where <x, y> is a pair of coordinates in the new (projected) coordinate system.

1.7.3.1 Classification of Map Projections Representing the earth’s surface in two dimensions causes distortion in the shape, area, distance, or direction of the data. Different projections cause different types of distortions. Some projections are designed to minimize the distortion of one or two of the data’s characteristics.

Generally, there are three levels of recognition for map projections: Class, aspect and property Class:  The Cylindrical projection  The Planar (Azimuthal) projection © Binyam Tesfaw Hailu, PhD AAU 2017

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GIS Practical Training, ArcGIS 10.5 

The Conical projection

Properties:  Conformality-angle preserved  Equivalence (Equal Area)- area preserved  Equidistance-equal distance in one direction Aspect:   

The normal aspect The transverse aspect The oblique aspect

There are more than 400 different types of map projections in use today. Most of them are based on one of the above classes and inherit their properties. Mostly it is possibly to convert data from one projection to the other providing we know the parameters associated with it. In the naming of a given map projection, the class, aspect and property of the projection together with the name of the originator and the modifications, in any, are specified. Some examples include: Normal cylindrical equal-area (Lambert), Normal cylindrical equal-area (Behrman), Lambert Azimuthal Equal Area, Albers Conical Equal Area, etc.

Cylindrical Projection

Conical Projection © Binyam Tesfaw Hailu, PhD AAU 2017

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Planar (Azimuthal) Projection Figure 8.5 Different types of Map projections

1.7.3.2 Parameters of Map Projections A map projection by itself isn’t enough to define a projected coordinate system. Each map projection has a set of parameters that must be defined. The parameters specify the origin and customize a projection for the area of interest. Angular parameters use the geographic coordinate system units, while linear parameters use the projected coordinate system units.

Linear Parameters include: False easting-A linear value applied to the origin of the x-coordinates.

False northing-A linear value applied to the origin of the y-coordinates. False easting and northing values are usually applied to ensure that all x or y values are positive. You can also use the false easting and northing parameters to reduce the range of the x- or y-coordinate values.

Scale factor-A unitless value applied to the center point or line of a map projection. The scale factor is usually slightly less than one. The UTM coordinate system, which uses the Transverse Mercator projection, has a scale factor of 0.9996. Rather than 1.0, the scale along the central meridian of the projection is 0.9996. This creates two almost parallel lines approximately 180 kilometers away, where the scale is 1.0. The scale factor reduces the overall distortion of the projection in the area of interest.

1.7.3.3 Selecting a suitable map projection The selection of map projection for GIS will be influenced by the following:   

How the results of analysis are best presented in the from of a map Before it is possible to match different data layers in GIS, all maps must be transformed to one common map projection In order to make any quantitative measurements (area, length, etc) the degree of accuracy must be examined

General rules for selecting a projection  Tropical country—cylindrical projection © Binyam Tesfaw Hailu, PhD AAU 2017

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GIS Practical Training, ArcGIS 10.5  

Temperate country—conical projection Polar regions—azimuthal projection

1.7.4 The Universel Transverse Mercator (UTM) system:       

developed in the late 1940s by the US Army the projection is the ‘Gauss-Kruger’ version of the Transverse Mercator-equidistant cylindrical projection Intended for mapping areas : 840N – 800S Unit of measure is meter The world is divided into 60 zones of 60 of longitude in width (Fig. 8.6) Zone 1 starts at 1800 W and Each zone has its own coordinate system A second zoning is made along the latitudes following 80 intervals (except the northern most zone-120)- they are given letters from C, D, E, …

Figure 8.6 The UTM system

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   

The easting of the origin of each zone is assigned a value of 500,000 The northing: for the Southern hemisphere the equator is assigned a northing value of 1,000,000 m, while for the Northern hemisphere it is 0 (Fig. 8.7).

The UTM might use one of the following spheroid: International, Clarke 1880 (Africa), Clarke 1866 (N. America), Everest or Bessel (Asia) When there is a map that covers more than one UTM zone, the zone that occupies the major part of the map (the middle zone) is used, extending the borders of the zone over the +30 and -30 boundaries.

2 Exploring ArcCatalog, ArcMap 10, and ArcToolbox 2.1 Exploring ArcCatalog (Day-2) The ArcCatalog application helps you to organize and manage all of your GIS data. It includes tools for browsing and finding geographic information, recording, and viewing metadata, quickly viewing any dataset, and defining the schema structure for your geographic data layers 2.1.1 Viewing data in ArcCatalog

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1. Start  All Programs  ArcGIS  ArcCatalog.

2. In the catalog tree navigate to “D:”drive and click the plus sign next to it to expand the contents.

3. Click the plus sign next to folder “AFERIA-2017” to view the contents of the folder, and then click “Amhara_Zone” shapefile 4. Click preview tab. Now the “Amhara_Zone” shapefile is displayed

The title bar displays the location of the selected item

ArcCatalog tree

5.

Preview Click the Preview dropdown arrow and click Table.

Now you can see the feature attribute table for the “Amhara_Zone” shapefile To view the description (i.e. metadata: data about data)  Click description tab, then  Click Description  for example, purpose of the data

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Ex. Apply the above procedure for the rest of the data in “AFERIA-2017” folder

2.1.2 Connecting to your data When you start ArcCatalog for the first time, the Catalog tree has a branch for each local hard drive. Branches for coordinate systems, database connections, geocoding services, Internet servers, and search results can be added by clicking the Tools menu and clicking Options, then checking the check boxes next to the branches you want to add to the Catalog. You can view the contents of a branch by double-clicking it or by clicking the plus sign beside it.

You can also create new branches in the Catalog tree to make it easier to navigate to your data. These branches are called connections.

Making a connection to Folder Now you will add a connection to the folder that contains the tutorial data. This new branch in the Catalog tree will remain until you delete it.

1. Click the Connect to Folder button. When you click the button, a window opens that lets you navigate to a folder on your computer or to a folder on another computer on your network.

2. Navigate to the folder you are working on the drive where the tutorial data is installed. Click OK. The new connection shows up as a branch in the Catalog tree.

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2.1.3 Managing your data in ArcCatalog 2.1.3.1

Creating a new folder

1.

Right-click “D:” drive point to New, and click Folder.

2.

Rename the folder by typing “AFERIA-2017” over the highlighted text.

3.

Press Enter.

2.1.3.2

Copying an item

1. Click “AFERIA-2017” folder to list its content 2.

Select all contents “AFERIA-2017” and click the Copy button (Ctrl + C) or right-click on the selected files to copy the files 3.

Click the “AFERIA-2017” folder in the drive and click the Paste button (Ctrl + V).

4.

C lick on “AFERIA-2017” in the drive and see data copied to the folder 2.1.3.3

Renaming an item

1. Click “River” in the folder “AFERIA-2017” then click File and click Rename by typing “Amhara_river” then press Enter 2. Or right Click River in the folder “AFERIA-2017” and rename by typing “Amhara_river” then Press Enter 2.1.3.4

Deleting an item

1. Click the “RoadsCopy”shapefile in the folder”AFERIA-2017” 2. Click the Delete button to delete.

3. Or right click the “RoadsCopy”shapefile in the folder “AFERIA-2017” and delete

Note: Once you delete an item you cannot undo the delete. So, be careful!

2.2

Exploring ArcMap 10 (Day-2)

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GIS Practical Training, ArcGIS 10.5 ArcMap 10 is the primary ArcGIS application for displaying, querying, editing, creating, and analyzing data.

2.2.1 Displaying and viewing Spatial Datasets in ArcMap 10 1. Start  All Programs  ArcGIS  ArcMap 10 Or if you have a shortcut for ArcMap 10 on your desktop double- click to start it

2. The ArcMap 10 10 startup dialog appears  click on ‘Blank map’, click

OK

An empty ArcMap 10 window appears Notice the following window with its various components.

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GIS Practical Training, ArcGIS 10.5 There are different ways of accessing commands in ArcMap 10: using the Menu bar, Toolbar and short cuts.

Click to Add data Tool Bar

T O O L S

Menu Bar

Table of Contents

Display Window

3. Click "Add data" button on the ArcMap 10 toolbar to add data 4. In the add data dialog navigate to D:\AFERIA-2017\ 5. Click Amhara_Wereda, river, Amhara_Zone from respective folders click Add data to display Or you can drag and drop these data from ArcCatalog.

6. Right-click on river and Amhara_Zone one by one and click remove to remove the data from ArcMap 10.

2.2.2 Exploring data in ArcMap 10 You can explore a map in several ways. The Tools toolbar contains frequently used tools that let you navigate around the map, find features, and get information about them.

1. Click the Zoom In button and Drag a box around one of the files in ArcMap 10 to zoom in to it. When you drag a box on the map after clicking the Zoom In button, the map zooms to the new area.

2. Click the Zoom out button to reduce the size of your map 3. click the Back button to jump back to the previous map extent 4. Click the Full Extent button the full extent of the map.

5. Use the pan tool in the display window

and see

and move the map

6. Use the selection tool to select features on your map © Binyam Tesfaw Hailu, PhD AAU 2017

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GIS Practical Training, ArcGIS 10.5 Take measurement 1. Display ‘Amhara_Wereda’ in ArcMap 10 2. Right-click in the display window of ArcMap 10 and click properties

3. In the ‘Data Frame Properties’ click General tab and set Display unit to Kilometers 4. Click Ok 5.

Place the measure

too at one corner of Amhara_Wereda and click once

6. Move the pointer to the other corner and double click. The distance is reported on the status bar Note: You can save your work as a map document.

Click on File  Save  Browse to your working directory and type “My First Doc”  Ok The Next time you start ArcMap 10 click on “An Existing Map” and  “My First Doc”

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2.2.3 Referencing data on a map When you add data to a map, the path to the data is stored in the map. You can view the path of the data represented by a layer in your map by looking on the Source tab of the table of contents or by double-clicking the layer to open the Properties dialog box, then checking the path on the Source tab of the dialog box.

When you open your map, ArcMap locates the data it needs using these stored paths. If ArcMap can't find the data for a particular layer, the layer will appear in the ArcMap table of contents but it won't be drawn. Instead, a red exclamation mark will appear next to the layer to indicate that the layer needs to be repaired. To learn how to update the path to the data so that the layer can be drawn,. If you are unable to repair a layer, you can either leave the unrepaired layer in the map until you can access the data, or you can remove it.

2.2.3.1 Repairing broken data links  Locate the layer with the broken link in the table of contents.  It will have a red exclamation mark next to it and its check box will be unavailable.  Right-click the layer and click Properties.  Click the Source tab.  Click the Set Data Source button, navigate to the data source you want, and click Add.  Click OK. ArcMap repairs the current layer

2.2.3.2 Storing relative pathnames to data for a map  Click the File menu and click Document Properties.  Click Data Source Options.  Click Store relative pathnames and click OK on all dialog boxes.  Save the map.

2.2.4

Changing how features are drawn

1. Right-click Amhara_Wereda in the ArcMap 10 table of contents and click Properties.

2. Click the Symbology tab on the Properties dialog © Binyam Tesfaw Hailu, PhD AAU 2017

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GIS Practical Training, ArcGIS 10.5 box. Click Categories, and then click unique values.

3. For fields Value click WEREDA and click Add All values 4. Click OK 2.2.5 Adding labels to a map 1. Right-click Amhara_Wereda in the table of contents.

2. Click properties 3. Click the Labels tab of the Layer Properties dialog box.

4. Click the dropdown arrow to select the label field and 5. Click Apply.

6. Check Label Features in this layer in the upper-left Corner of the dialog box and click OK. 2.2.6 Displaying Attribute tables behind the maps 1. Right-click on the Amhara_Wereda from the Table of contents 2. Click Open Attribute Table 3. Click on the left-most cell at the beginning of a row to select it

4. Click the Selected button to move all of the selected records to the top so that you can view the information easily.

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GIS Practical Training, ArcGIS 10.5 To clear what is selected, go to the Selection menu, Clear Selected Features. This will not remove the features, but just unselects them.

5. Close the attribute table

2.2.7 2.2.7.1

Querying data in ArcMap 10

Querying a map using the identify button

1. Click on the button from the ArcMap 10 tools 2 Click anywhere inside Amhara_Wereda map 3. An information window pops up with info about the selected feature 2.2.7.2

Querying a map using the Find tool

1. Click the Find tool 2. In the find window, for find click Adama 3. For in, click Amhara_Wereda 4. Right-click a raw in the context menu, then ‘Select feature(s)’ option. The feature is selected

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2.2.7.3

Exporting the Selected data

Once you have selected a feature from a layer, you can export only the selected features to a new file. To do so: 1. Right click on Amhara_Wereda in the table of contents 2. Click Data then click Export Data 3. Then navigate to D:\Amhara_reg then type SEMEN Showa as output file name

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GIS Practical Training, ArcGIS 10.5 2.2.8 2.2.8.1

Advanced Query (Day 3)

By Attributes

1. On the menu bar , click selection  Select By attributes 2. For Layer, click Am_zones 3. Method: Create a new set 4. Double-click on “ZONES” in the Fields box 5. Click the ‘=’ sign once from the list of operators 6. Click the complete list button under the Unique values list box 7. For unique values, doubleclick SEMEN SHOWA 8. Click Apply 9. If any syntax error, click Clear and start again In the display areas; observe that SEMEN SHOWA is highlighted 10. On the select by attribute dialog, click Close.

2.2.8.2

By Location

While the SEMEN SHOWA is still selected On the menu bar, click selection  Select By Location 2) In the field I want to: choose ‘select features from’ 3) Check Amhara_Towns under ‘the Target layer (s)’ 1)

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GIS Practical Training, ArcGIS 10.5 In the field that: select, ‘Target layer(s) features are completely within the source layer feature’ 5) In the field Source layer: select, ‘SEMEN SHOWA’ 6) Click Apply, Close.

7) On the menu bar click Selection, and then click Clear Selected Feature. This unselects the selected features!

4)

In the display areas; observe that all Amhara_Wereda in SEMEN SHOWA are highlighted.

Ex: Do the same for other zones.

3 Cartographic applications of ArcGIS (day 3) 3.1 Working with Symbology in ArcMap 10 3.1.1 Classifying data ArcMap 10 provides various means of symbolizing your data.

3.1.1.1

Setting a standard classification method

1. Start ArcMap 10 and add Amhara_Towns to your ArcMap 10 2. Right-click on Amhara_Towns in the table of contents and click Properties.

3. Click the Symbology tab and click Quantities.

4. Click the Value dropdown arrow and click POPTOT ArcMap 10 divides this field into the Value to create a ratio.

5. Click Classify.

6. Click the Method dropdown arrow and click the classification method you want to use (in this case use Natural Breaks).

7. Click the Classes dropdown arrow and click © Binyam Tesfaw Hailu, PhD AAU 2017

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GIS Practical Training, ArcGIS 10.5 the number of classes you want to display (in this case use 5).

8. Click OK on the Classification dialog box.

9. Click OK on the Layer Properties dialog box

3.1.1.2 Editing a class range 10. Right-click Amhara_Wereda in the table of contents and click Properties.

11. Click the Symbology tab.

12. Click the Range you want to edit.

13. Make sure to click the Range, not the Label.

14. Type a new value.

15. This sets the upper value of the range.

16. Click OK.

3.1.1.3 Deleting a class break 17. Right-click the Amhara_Wereda in the table of contents and click Properties.

18. Click the Symbology tab and click Classify.

19. Click the class break you want to delete.

20. The selected break is highlighted.

21. Right-click the histogram and click Delete Break, then click OK

3.1.1.4 Excluding features from the classification 22. Right-click Amhara_Wereda in the table of contents and click Properties.

23. Click the Symbology tab and click Classify.

24. Click Exclusion.

25. Double-click POPTOT on the Query tab.

26. Click an operator (<=).

27. Click Get Unique Values and double-click 9999.

28. Click OK to execute the expression and exclude values.

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3.2 Symbolizing data in Arc map 3.2.1 Symbolizing point data 1. Click Amhara_Towns symbol in the table of contents of ArcMap 10, and then symbol selector is displayed 2. From symbol selector, select Triangle1 by clicking on it once, 3. Click on the properties tab, and then edit your symbol in the symbol property editor 4. Click OK

3.2.2 Symbolizing linear data 1. Click Road symbol in the table of contents of ArcMap 10, then symbol selector is displayed 2. From symbol selector, select Major Road by clicking on it once, and click on the properties tab, then edit your symbol in the symbol property editor 3. Click OK

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3.2.3 Symbolizing areal data 1. Click Amhara_Zone symbol in the table of contents of ArcMap 10, and then symbol selector is displayed 2. From symbol selector, Grey symbol by clicking on it, and then click on the properties tab, then edit your symbol in the symbol property editor 3. Click ok

3.2.4 Create custom symbols You can use the Style Manager to create a new symbol from scratch or you can modify an existing symbol. The Style Manager lets you organize styles and their contents (symbols and map elements). You can cut, copy, paste, rename, and modify any style contents and you can create new styles, symbols, and map elements.

1. Click the Customize menu, and then click Style Manager.

2. Double click on your working directory.

3. Click the Style type in the left panel (eg./ Marker Symbols) 4. Right Click anywhere in the right panel, then click Create New and edit properties.

5. Navigate to the program’s Styles folder.

6. Type the name for the new style you’re creating.

7. Click Save.

To modify an existing symbol, right-click on it in the style manager and access its properties.

Both actions will activate the Symbol Property Editor that will allow you to set the type of symbol, the color, style, size, and so forth, for each layer that will comprise the symbol. © Binyam Tesfaw Hailu, PhD AAU 2017

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4

Georeferencing Scanned Data (Day 4)

Raster data is commonly obtained by scanning maps or collecting aerial photographs and satellite images. Scanned map datasets don't normally contain spatial reference information (either embedded in the file or as a separate file). With aerial photography and satellite imagery, sometimes the locational information delivered with them is inadequate and the data does not align properly with other data you may have. Thus, to use some raster datasets in conjunction with your other spatial data, you may need to align, or georeference, to a map coordinate system. A map coordinate system is defined using a map projection (a method by which the curved surface of the earth is portrayed on a flat surface).

When you georeference your raster dataset, you define its location using map coordinates and assign a coordinate system. Georeferencing raster data allows it to be viewed, queried, and analyzed with other geographic data.

The general steps for georeferencing a raster dataset are: 1. Add the raster dataset that you want to align with your projected data in ArcMap. 2. Add control points that link known raster dataset positions to known positions in map coordinates.

3. Save the georeferencing information when you’re satisfied with the alignment (also referred to as registration).

4. Optionally, permanently transform the raster dataset.

4.1 How to Georeference a raster dataset 4.1.1 Georeferencing a raster dataset 1. Start ArcMap. 2. Add the layers residing in map coordinates and the raster dataset you want to georeferene.

3. In the table of contents, right-click a target layer (the referenced dataset) and click zoom to Layer.

4. From the Georeferencing toolbar, click the Layer drop-down arrow and click the raster layer you want to georeference.

5. Click Georeferencing and click Fit To Display.

This will display the raster dataset in the same area as the target layers. You can also use the Shift and Rotate tools to move the raster dataset as needed. To see all the datasets, you may have to adjust their order in the table of contents.

6. Click the Add Control Points tool to add control points.

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7. To add a link, click the mouse pointer on a known location on the raster dataset, then on a known location on the data in map coordinates (the referenced data).

You may find it useful to add your links in a

Magnification window. When working with two raster datasets, you may want to open the Effects toolbar and adjust the transparency or turn layers on and off in the table of contents to view each image as you add your links.

8. Add enough links for the type of transformation.

You need a minimum of three links for a spline or 1st-order polynomial (affine), six links for a 2nd-order polynomial, and ten links for an affine or 3rd-order polynomial.

9. Click View Link Table to evaluate the transformation.

You can examine the residual error for each link and the RMS error. If you’re satisfied with the registration, you can stop entering links.

10. Click Georeferencing and click Update Georeferencing to save the transformation information with the raster dataset.

This creates a new file with the same name as the raster dataset but with an .aux.xml file extension. It also creates a world file for some of the file formats, including .tif and .img files.

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4.1.2 Entering specific x, y map coordinates 1. Click View Link Table on the Georeferencing toolbar.

2. Click the Add Control Points tool .

3. Click the mouse over the known location in the unreferenced image to add the first coordinate in the link.

4. Right-click the image and click Input X and Y. 5. Enter the reference coordinates on the Enter Coordinates dialog box.

6. Click OK. Exercise: Georefernce the scanned topo sheet of Addis Ababa NE.

5 Editing and data compilation Compiling geographic information is the most costly and time consuming part of developing a GIS. The geographic information that is created is a valuable but time sensitive asset, so care and precision must be taken in its collection and maintenance. GIS data loses its value if it becomes out of date. The database must be updated to keep it current. Just as the owner of a parcel changes when it is sold, the geometry of the parcel feature itself may change if it is split for subdivisions. Even natural features change over time: the course of a river may change through meandering or by stream capture.

To minimize the cost of data development and necessary updates, it is important that the tools and workflows for data compilation be as streamlined and productive as possible. ArcGIS has a complete data compilation toolset. ArcMap is the application for creating and editing geographic data. ArcMap contains tools that help you construct features quickly and easily while maintaining the integrity of your data. For organizations that need multiple users to simultaneously edit a shared geodatabase, ArcMap and ArcSDE provide the tools necessary to manage versions and resolve potential conflicts.

ArcGIS allows you to create and edit several kinds of data. In general terms, the feature geometry you can edit includes points, lines, polygons, text (annotations and dimensions), multipatches, multipoints, shared edges and nodes from a topology or geometric network, and tables. Some types of data, such as CAD drawings or coverages, can be viewed but not edited inside ArcMap, and must be edited in the data's native application. For example, while you can view coverages in ArcMap, you can only edit them in ArcInfo Workstation. You can import these display-only formats into geodatabase feature classes or shapefiles and edit them in ArcMap. Whether you're using ArcView, ArcEditor, or ArcInfo, you use the same editing tools in ArcMap to work on your geographic data. Certain editing operations may require additional licensing, such as ArcEditor, ArcInfo, or an ArcGIS extension. For example, ArcView allows you to display but not create or edit some geodatabase capabilities, such as topologies, dimensions, geometric networks, and data in an ArcSDE geodatabase.

The process of compiling and editing data in ArcGIS can be divided into two categories of operations: collecting data and integrating data. Data collection involves entering new data into your GIS, while data integration involves transforming data and maintaining its integrity.

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5.1 Methods of collecting data 5.1.1 Digitizing data Digitizing, the process of converting features into a digital format, is one way to create new data. There are several ways to digitize new features. These include digitizing "on screen" or "heads up" over an image, digitizing a hard copy of a map on a digitizing board, or using automated digitization.

Interactive, or "heads up" digitization, is one of the most common methods. In this method, you display an aerial photograph, satellite image, or orthophotograph onscreen as a basemap and trace features, such as roads, buildings, or parcels from it.

In hardcopy digitizing, you use a digitizing table connected to a computer that converts positions on the table surface into digital x,y coordinates as you trace them with a handheld puck (a pen or mouse-like device).

Automatic digitization is another method of digitizing features. The ArcScan for ArcGIS extension enables you to perform automatic or interactive raster-to-vector data conversion with high precision, with little or no operator intervention during the data capture stage.

5.1.2 Collecting data in the field Some GIS data is directly captured in the field using a Global Positioning System (GPS) device.

GPS units calculate their position using signals from satellites (and sometimes base stations).

They vary in capability and accuracy, so be sure to use a GPS that is as accurate as the data with which it will be used. GPS units can be connected to handheld computers, laptops, or Tablet PCs to record data in the field.

Handheld computing devices allow you to run ArcPad software, which provides database access, mapping, GIS, and GPS integration to users out in the field by handheld and mobile devices. You can extract data from a geodatabase to use in the field with ArcPad, and then you can update your geodatabase with the changes you made in ArcPad. If you use a notebook 34 © Binyam Tesfaw Hailu, PhD AAU 2017

GIS Practical Training, ArcGIS 10.5 computer or a Tablet PC in the field, you can bring the actual geodatabase and its full capabilities with you.

5.2 Workflow for creating and editing features Before you create or edit features in ArcMap, you need to have an existing feature class to edit.

If you don't have one, you can create a new geodatabase feature class or a shapefile in ArcCatalog.

1. Open ArcCatalog 2. Right click on the feature dataset 3. Point to new 4. Create feature class 5. Add the name of the feature 6. Addd some field names you need to add to the feature class 7. Click finish

The Editor Toolbar contains the various commands you will need to edit geographic features in your database. You must add the Editor toolbar to ArcMap before you can begin editing.

Once you have added the data you want to edit to ArcMap, you'll follow a basic workflow.

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GIS Practical Training, ArcGIS 10.5 1. Choose the workspace and data frame you want to edit.

2. Start an edit session (start editing).

3. Choose which layer within your workspace you want to be the target of your actions (the target layer).

4. Choose whether you want to create new features or edit existing ones.

5. Set up additional properties or options, such as turning on snapping, setting which layers are selectable, and specifying input units.

6. Choose a tool. The Editor toolbar contains the most frequently used simple-feature editing tools. Additional toolbars contain tools for editing topologies, geometric networks, routes, and annotation features.

7. Add or edit attributes of the feature.

8. Save edits and stop editing.

This workflow is described in more detail in the next section.

Most of the time you will edit data in data view, since it shows only the data in your map and hides the layout elements. You can edit in layout view, although editing is typically easier and more accurate in data view. However, editing in layout view is useful when you want to make additions and modifications to your map in the context of your map layout. For example, suppose in data view, you have added some text that identifies an ocean, but in layout view, you see that the text is too close to the edge of the data frame. To correct this, you can simply put the data frame into focus and move the piece of text while you're still in layout view, rather than switching between views.

5.2.1 Choosing the workspace and starting an edit session Editing applies to a single workspace in a single ArcMap data frame, where a workspace is a geodatabase or a folder of shapefiles. If you have more than one data frame in your map, you can only edit the layers in one data frame—even if all data is in the same workspace. ArcMap can display data stored in different coordinate systems in the coordinate system of a data frame.

Although you can edit data in different coordinate systems, it is generally best if all the data you plan to edit together has the same coordinate system.

Editing occurs in an edit session. During an edit session, you can create or modify vector features or tabular attribute information. When you want to edit, you need to start an edit session, which you end when you're done. Edits are temporary until you choose to save and apply them permanently to your data. You can also quit an edit session without saving your changes. Just saving a map document does not save the edits to the features—you need to specifically save the edits in your edit session.

When you save edits, you write them to the data source, or a database. When you are working with data in a database, making edits and saving them are transactions against the database.

Versions allow multiple users in a multiuser geodatabase to edit the same data without applying feature locks or duplicating data. When users are ready to apply their edits, they will merge their changes through a process of reconciling edits, resolving conflicts, and posting their changes to the parent version of a database.

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5.2.2 Setting the target layer Once you have chosen the workspace that will be edited, many editing operations require that you specify the layer that will be the target for your edits. For example, when you are creating new features or modifying existing features, you need to set the target layer so ArcMap knows the layer you want to update. You must set the target layer whenever you create new features— whether you're creating them with the Sketch tool, by copying and pasting, or by buffering another feature, as some examples. You set the target layer with the drop-down list on the Editor toolbar, rather than the table of contents. Highlighting a layer in the table of contents has no effect in the ArcMap editing environment.

The Target layer drop-down list (shown below) contains the names of all the layers in the datasets with which you're working. Subtypes are also listed, if applicable. For instance, if you set the target layer to Parcels : Non-Residential, any features you create will be part of the NonResidential subtype of the Parcels layer.

When you choose a certain layer as the target, certain geodatabase properties are carried over to the ArcMap editing environment. For example, when you create a new feature in a layer based from a feature class with geodatabase domains specified, these attributes will automatically be present in the new feature. Similarly, when you choose an annotation layer as the target, the display properties of color, size, font, and so on you've specified for the geodatabase feature class will automatically be set up for you.

Some operations do not require a target layer, since they obtain their settings from other properties in ArcMap. For example, you do not need to specify a target layer when you simply want to select a feature, then move, rotate, or edit its vertices. In cases of selection, for example, the ArcMap editing tools adhere to the ArcMap settings, such as selection options and which layers are selectable.

5.2.3 Choosing an edit task The editing operations you can use on features are called edit tasks. One of the most common tasks is to create new features. The tasks are categorized based on their general function, such as to create data, modify data, and work with topology. You specify the task from the drop-down list on the Editor toolbar. You can customize the task list by adding and removing tasks, based on the needs of your project. In addition, you can use programming to develop your own editing tasks.

5.2.4 Choosing a tool and creating an edit sketch In ArcMap, you use an edit sketch to create or modify the shape of features. An edit sketch is a temporary representation of a feature that allows you to edit its geometry.

A sketch is composed of all the vertices and segments of © Binyam Tesfaw Hailu, PhD AAU 2017

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GIS Practical Training, ArcGIS 10.5 the feature. Vertices are the points at which the sketch changes direction, such as corners; segments are the lines that connect the vertices.

When you want to create new features or draw a sketch, you'll most commonly use the Sketch tool and the tools on the Editor toolbar tool palette. With those tools, for example, you can create lines, arcs, and tangent curves, vertices at intersections or midpoints, vertices based on distances and directions from other features, or new segments by tracing along existing ones.

The Sketch tool has an accompanying shortcut (context) menu that helps you place vertices and segments more accurately.

For example, you can add a vertex at a specific x,y location, draw a segment at an exact length and direction, or make a segment parallel or perpendicular to another segment. You can also setup any additional options for editing, such as turning on snapping.

When you create the vertices in a sketch (typically, by clicking with your mouse), the segments between vertices are added automatically. Once you're satisfied with the shape of the sketch, you need to finish the sketch to complete the feature's geometry and actually create the feature.

There are several ways that you can finish a sketch, including double-clicking with your mouse, choosing the command from a shortcut menu, or using a keyboard shortcut (F2).

The left graphic below shows the polygon feature being constructed from an edit sketch. Once all the desired vertices are added, the sketch is finished and it becomes a feature. You can double-click a feature with the Edit tool to modify the sketch (thus, changing the shape of the polygon).

To create a new polygon with the Sketch tool, for example, at least three vertices are required.

To create a new line, at least two vertices—the start and end points—are required to finish the sketch, and therefore, create the feature. A sketch of a line records the direction it was digitized, which is important if you need to trim or extend the line or perform an operation on it that uses measurements originating from the start or end point. You can flip the direction of a line so the last vertex of the sketch becomes the first. Vertices are marked in green, with the last vertex added marked in red.

Sometimes, you need to create a feature that has more than one physical part but only references one set of attributes in the database. These are called multipoint for point or multipart for line and polygon features. A system of oil wells could be represented by a multipoint feature, which can only be created in a feature class with multipoint geometry. (The multipoint geometry type © Binyam Tesfaw Hailu, PhD AAU 2017

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GIS Practical Training, ArcGIS 10.5 is set when you create a new feature class.) Multipoint layers are created as sketches. Similarly, a group of islands could be represented as a multipart polygon feature. To create a multipoint or multipart feature, you need to finish each part first, then finish the whole sketch once you have created the individual parts.

5.2.5 Examples of edit tasks and sketches used together You can use the tasks in conjunction with a sketch you create to edit your geographic data in ArcMap. Here are some examples:   

The Create New Feature task uses a sketch you create to make the new feature.

The Select Features Using a Line task uses a sketch you create to select features; the features the line intersects are selected.

The Cut Polygon Features task uses a line sketch you draw to cut a polygon.

5.2.6 Editing existing features with sketches In addition to constructing new features, sketches can be used to modify existing features. For example, to reshape a polygon, you can construct a sketch of the new edge, or you can use a sketch to divide one polygon into two.

You can insert or delete vertices in a sketch to modify a feature's shape. You can also trim and extend lines, and split lines and polygons by drawing a sketch. When you use a sketch to modify an existing feature, you complete the update by finishing the sketch.

5.3

Adding attribute information

Attributes are descriptions of a geographic feature in a GIS, usually stored as a row in a table.

For example, attributes of a river might include its name, length, and average depth. You can enter new attribute values when you create features, and you can edit existing values. When you create a new feature, it starts with only the default attribute values. You input attributes after you create a feature.

You add and modify the attributes of features within an edit session. You can edit attribute values manually by typing in new values or by copying and pasting existing values. Some features are designed with subtypes, default values, and attribute domains. These can make it easier to edit values and can help prevent data entry errors. After you modify attributes that have © Binyam Tesfaw Hailu, PhD AAU 2017

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GIS Practical Training, ArcGIS 10.5 range domains, you can validate your edits to check that the new values fall within the valid range.

If there are relationships between feature classes and tables in your geodatabase, you can find the objects related to a particular object and edit them. For example, if you have a table of land owners that is related to a parcel feature class, you can select a parcel feature, use the relationship class to find the owner of that parcel, then edit some of the attributes in the owner table. Some relationship classes have rules that control how features can be related. After you edit related geodatabase features or tables that have relationship rules, you can validate your edits to check that the related objects still conform to the relationship rules. You can also establish a new relationship between objects or break existing relationships.

5.3.1 Methods of editing attributes There are two main ways of adding or updating attributes in ArcMap: 1. The Attributes dialog box and 2. The table window.

The Attributes dialog box displays attributes of selected features, and shows you the raw data and fields as they are stored in your geodatabase.

1. Click on Attributes button from the Editor tool bar 2. The left side of the dialog box shows the name of the layer to which the selected feature or features belong, while the right side shows the attribute values.

The table window displays the attribute for the edited feature class 1. Right click on the layer from the data frame 2. Click on the open attribute table 3. Edit the field which can be edited. (Note that The editing should be in editing mode) © Binyam Tesfaw Hailu, PhD AAU 2017

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5.4 The snapping environment Snapping is one of the easiest ways to more accurately position new vertices and segments, as well as when you're moving features. Snapping can help establish exact locations in relation to other features. When snapping is turned on, your mouse pointer will jump, or snap to, edges and vertices when your pointer is near them. This means the pointer is within the snapping tolerance. Snapping can help you with many editing operations; for example, creating polygons that do not overlap or have gaps between them or placing a point exactly along an existing line.

Methods are A) Snapping tool bar B) Options A)

1 1.

2.

3.

4.

2

3

4

Point Snap setting End snapping Vertex snapping Edge snapping

B)

5.5 Editing shared geometry You may find that you need to edit the geometry of multiple features at once.

Using the topological association among features, you can move boundaries and vertices shared by multiple features. For example, you can move a border to update two forest polygons or, as seen in the graphic below, move a corner vertex © Binyam Tesfaw Hailu, PhD AAU 2017

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GIS Practical Training, ArcGIS 10.5 and update several parcel polygons and a few lot boundaries at the same time.

5.5.1 Completing polygons using existing polygon geometry 1. Click the Construction tools and click Auto-Complete Polygons.

2. Click the polygon feature class to which you want to add polygons.

3. Click the Sketch tool 4. Start an edit sketch.

.

Starting from the boundary of an existing polygon, use the Sketch tool to digitize a boundary of the new polygon that will share a boundary with the existing polygon.

Once you've started the edit sketch, you can use any of the tools on the sketch tool palette to create your edit sketch.

You can either snap the edit sketch to the edge of the existing polygon or start and finish the sketch just inside the existing polygon.

5. Right-click anywhere on the map and click Finish Sketch.

The new polygon is created from the boundary you digitized and the existing polygon's boundary

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5.5.2 About splitting polygon features (Cut Polygon Features) To split polygons, use the Cut Polygon Features task, then draw a line sketch across the polygon. The cut operation updates the shape of the existing feature and creates one or more new features using the default attribute values for the feature class.

Below shows a polygon feature that is cut into two features where the line is sketched.

When you are splitting polygons, make sure your sketch cuts completely through the selected polygon. Turning on edge snapping often helps ensure that the cut operation is completed successfully.

5.5.3 How to split polygon features Splitting polygons by drawing a sketch 1. Click the Edit tool .

2. Click the polygon you want to split.

3. Click Cut Polygon Features.

4. Click the tool palette drop-down arrow and click the Sketch tool .

5. Construct a line sketch that cuts the original polygon as desired.

6. Right-click anywhere on the map and click Finish Sketch.

The polygon is split into two or more features.

6 Presenting data (Day 5) 6.1 Preparing map layout A map is composed of one or more data frames (and data) arranged on the page, plus one or more other map elements. Simple maps usually have only a single data frame.  Open ArcMap 10  Navigate to D:\AFERIA-2017and Add Amhara_zones, Amhara_road, Amhara_town, Amhara_rivers and Lakes © Binyam Tesfaw Hailu, PhD AAU 2017

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GIS Practical Training, ArcGIS 10.5  Save your map as a map document (.mxd)  Click File and click Save As.  Navigate to the AFERIA-2017folder.  Type “Amhara_Zone”. Click Save.  Classify, symbolize and Label the displayed data.

Here, you can’t manage your Labels since they are not editable in ArcMap 10, therefore; you have to change labels to annotation to edit as you like. Follow the following procedures to convert labels to annotation 6.1.1 Converting labels to map document annotation 1. In the ArcMap 10 table of contents, right-click the Amhara_Zone after labeling it 2. Click Convert Labels to Annotation.

3. For the Store Annotation option, click in the map.

4. Click ‘features in current extent’ to create the annotation.

5. Click the name of the annotation group to change it. You can specify a new or existing annotation group.

6. Some labels may not currently display on the map because there is no room for them. To convert these labels, check the Convert unplaced labels box. This saves the unplaced labels in the map document, allowing you to later position them one at a time.

7. Click Convert.

8. Double-Click annotation in the ArcMap 10, then you can modify it 9. Save your map 6.1.2

Switching to Layout View

Click View menu  Layout View or Click on layout button on the bottom screen of ArcMap 10. Notice that the menu bar changes Now you can change the page layout and other

features of your map.

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GIS Practical Training, ArcGIS 10.5 While viewing the layout, a Layout toolbar appears. These tools can be used to navigate around the map layout.

Note: Once you are in Layout view, you have to use this toolbar to zoom you map.

To move the maps inside the Layout data frame use the Pan button

© Binyam Tesfaw Hailu, PhD AAU 2017

from the Tools

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GIS Practical Training, ArcGIS 10.5

6.1.3 Setting the page size and printer properties 1. Right-click the Map and click, Page and Print Setup.

2. Click the Name dropdown arrow and click the printer you want to use.

3. Click the Printer Paper Size dropdown arrow and click 3A paper size 4. Checked The Use Printer Paper Settings.

5. Click Landscape orientation under Printer Setup Paper 6. Click OK.

6.1.4 Resizing and moving data frame 1. Click the Select Elements arrow button from the Tools ToolBar. 2. Click the data frame to select it.

The data frame is now outlined with a dashed line and has selection handles at its corners and edges.

3. Click the center of the data frame and drag it to the direction you want the layout.

4. Point to the © Binyam Tesfaw Hailu, PhD AAU 2017

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GIS Practical Training, ArcGIS 10.5 selection handle at the lower-right corner of the data frame. The mouse pointer becomes a two pointed resize arrow. Click the corner and drag it to any direction.

6.2 Inserting Legend, Scale bar, Title…

6.2.1 Adding a scalebar Click on View menu  Data frame properties Cilick on General tab Select Meters for both Map and Display  ok On the Insert menu, click Scale Bar. Click one of the scalebars and click OK. Click the scalebar and drag it to where you want to place 7. Resize it if needed 1.

2.

3.

4.

5.

6.

6.2.2 Adding a North arrow 1. Click the Insert menu and click North Arrow.

2. The North Arrow Selector dialog box appears.

3. Click one of the North arrows and click OK. 4. Click the North arrow and drag it to the empty space  resize if necessary 6.2.3 Adding a legend 1. Click the Insert menu and click Legend. The Legend Wizard appears.

2. You can select items to be included in your legend using the above window.

Select an item from the left and click > to add it to your legend. Select an item from the right and click < to remove it from your legend.

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GIS Practical Training, ArcGIS 10.5 3. Click Next several times to step through the wizard, accepting the default legend parameters. Click Finish when done.

4. The legend appears on your map.

5. Click the legend and drag it to the appropriate place.

6. Resize to appropriate size 7. Double-click on the legend to edit it.

You can modify the legend style, change number of columns for the legend for each element, …

6.2.4 Adding a title 8. Click the Insert menu and click Title.

9. Click the title and type “Secondary Weredas” 10. Resize as necessary

6.3

Inserting Grids and Graticules

Accessing the grid/graticule wizard 1. Click the View menu and click Data Frame Properties.

2. Click the Grids tab.

3. Click the New Grid button: Defining the graticule 4. In the grid/graticule wizard, click the Measured Grid option.

5. Type a name for the resulting grid.

This name will appear in the list of grids in the Data Frame Properties dialog box.

6. Follow the steps in the wizard and click Next as you complete each panel. © Binyam Tesfaw Hailu, PhD AAU 2017

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GIS Practical Training, ArcGIS 10.5 7. Click Finish.

Note: Once you have created Grids and Graticules, you can modify their properties: View  Data Frame Properties  Grids  click on the Grid or Graticule  Properties  Make your changes  OK

Graticule

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Measured

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6.4 Printing a map 1.

Click File and click Print. The Print dialog box appears. You can change the default printer by clicking Setup.

2. Click OK.

6.4.1 1.

2.

3.

4.

Saving a map as a map template Click the File menu and click Save As. Navigate to D:\AFERIA-2017and Type Wereda as a file name Click the Save as type dropdown arrow and click ArcMap 10 Template.

Click Save.

6.4.2 Exporting your map to other file formats 5. File  selects <Map Export> 6. When the export window comes up select “Export Format” as JPEG/EMF/Tiff/…. / 7. And give the output a “File Name” 8. Save your Map document 9. Exit ArcMap 10

6.5 Work with map templates 6.5.1 1.

2.

3.

4.

5.

Opening a temple when you first start ArcMap 10 Start ArcMap 10.

Click the option to start using ArcMap 10 with a template.

Click OK. Navigate to D:\AFERIA-2017and Click Zone.

Click OK

6.5.2 Opening a new template while in ArcMap 10

1.

2.

3.

4.

5.

Click the File menu and click New. Navigate to D:\AFERIA-2017and Click Zone OK. Remove data in the tamplate Add Amhara_Wereda, Rivers, Lakes to your layout and produce a map

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