GIS Fundamentals: Supplementary Lessons with ArcGISIntroduction to ArcGIS
Lesson 1: Introduction to ArcGIS
What You’ll Learn:
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GIS Fundamentals: Supplementary Lessons with ArcGISIntroduction to ArcGIS
-Start ArcMap
-Create a new map
-Add data layers
-Pan and zoom
-Change data symbology
-Change display properties
-Set relative paths
-Add layers to features
-Select data
-Measure distances
-Use raster
-Create map layouts to print
-Add legends, titles, North arrows, and other elements
-Print a map to a PDF
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GIS Fundamentals: Supplementary Lessons with ArcGISIntroduction to ArcGIS
Data for this exercise are located in the L1 subdirectory or the class web page.
Videos for this exercise are located in the class web page.
What You’ll Produce: Four maps, one of lakes and roads, one of wetlands, a third map of the Cloquet Forestry Center, and a fourth a map of topological errors.
Background: This is the first in a series of introductory exercises for ArcGIS/ArcMap. These are practical skills that complement the theory and practice of GIS described in the textbook “GIS Fundamentals: A First Text on Geographic Information Systems”, by Paul Bolstad.
We assume you have a functioning copy of ArcMap running on your computer. The exercises were developed with ArcGIS, ArcView version 10, student edition.
There are a set of videos that supplement these lessons. They will be referenced during the lessons, in bold. The first video,Start ArcMap, describes these first few steps.
Each lab assumes you have a copy of the lesson data files on a local drive.
Part 1: Starting ArcGIS, adding data and creating your first map
First, find the ArcMap icon, shown to the right. The icon is often located
1) as a desktop or taskbar shortcut,
or
2) in an ArcGIS folder
In Windows XP it may often by found by left clicking on the Start button in the lower left of the screen and selecting Programs ArcGIS ArcMap.
Double left click on the ArcMap icon, and be patient while a start banner displays. Depending on your startup option you may or may not see the ArcMap – Getting Started screen (below to the right). If you do get this window thenelect to open an existing map, create a new, empty map from a custom template, or from a standard template.
You indicate your choice by left clicking on the entry in the left pane, as shown.(Note: you may want to check the “Do not show this dialog in the future” as all of our labs begin with a Blank Map)
Now single left click on the OK button in the lower right corner of the popup window.
This will open the main ArcMap window, similar to that displayed at right. Note there is a Table of Contents window pane, a mostly blank area forming the left part of the screen beside a bar where various icons and menu bars, each of which allows you to perform some action.
Left click on the Add Data button in the top center of the screen to add data layers (also called themes).
You will see a dialog box to select a layer or layers for the map.
However, sometimes a directory or drive does not appear in the list of sources.
You may need to create a connection, using the Connect to Folder button, shown in the figure to the right.
This opens a list of available folders, at least those on your hard disk, and perhaps any additional available through your network. Navigate to the folder containing your data by clicking down the directory tree, and selecting the appropriate folder (shown at the right), in this case … \L1. Clicking OK makes this folder available, so that you may add data from it to your map.
This should open the L1 directory. If not, or in the future, you may navigate to a connected drive by clicking on the Add Data button (), then on the display triangle to the right of the “Look in:” sub window (see left), until you see your data folder, in this case named LabData\L1.
You’ll likely be using data that has be copied to your personal portable drive, so the directory tree and name may be different, but the important point is to know how to find your data, and add and navigate to directories.
Navigate to the L1 folder (shown here) and double left click on the file named lakes.shp. This will add this data layer to your map.
Note that the lakes.shp layer data are displayed in the data view pane, and data names are listed in the table of contents pane on the left.
Repeat the process to add the roads.shp data layer.
Panning and Zooming
ArcMap allows you to change the magnification and area that you view in your data pane. There is a cluster of zoom buttons (see at right). They are typically near the table of contents pane, but because the toolbars are “dockable”, the may be anywhere along the edge of the ArcMap window, and may be arranged horizontally instead of vertically, as shown here.
Left click on the zoom and pan icons to change cursor function. Left clicking on the plus (+) magnifying glass changes it to a “zoom in” cursor, then click on the data pane will zoom in on a point. You can also left click and hold/drag to define a zoom area.
The minus cursor zooms out, and the “arrows in” and “arrows out” buttons, found below the magnifying glass buttons, zoom the entire pane by a fixed amount.
Next there is a “pan” button, a hand, that does not change the magnification, but allows you to click/drag position the data. There is also a globe zoom button that zooms to the full “Extent” of your data. Below this are “arrows in” and “arrows out” buttons to zoom by fixed amounts, and buttons that zooms back and forth among previous zoom levels.
To exit the pan or zoom cursors, click on the arrow button near the cluster of the pan and zoom tools.
You may also specify a scale by typing into the scale window, along the top of the main menu bar:
Changing Data Symbology We can customize a layer’s appearance. Left double-click on a symbol icon, the colored patch below the name of the lakes data layer in the table of contents (see right).
Video: IntroSymbology Layout
The Symbol Selector window will appear (left).
You can select a symbol type from the examples on the left of the window, and change the properties with the controls on the right of this window.
Left click on the blue patch (shown highlighted in the figure on previous page), or another that suits your fancy, and left click on the OK near the lower right.
Repeat this process for the Roads layer.
Your map should look something like the picture to the right.
Within the data pane, there can be two “views” on the data. We have been working with the Data View. This is an uncluttered view, used primarily when we’re working with our data. There is also a Layout View, used to prepare maps for output. A layout view allows you to add a north arrow, scalebar, and other elements we usually expect to find on a printed or other published map.
You left click to switch between the Data View (icon near the lower left of the Data Pane, shown by the left arrow above) and the Layout View (icon, right arrow).
Note that second set of zoom tools that appear when we activate the Layout View (see below). These allow you to control the zoom and pan within the layout view, without changing the zoom in the data view.
Using the Layout View, Adding a Legend and North Arrow
Left click on the Layout View icon to prepare your map for printing.
SelectInsert from the list at the top of the main ArcMap menu (see figure at the right).
Left click to select Title from the drop down menu. A text box for typing a title appears on the layout view page.
Type in something logical; for example “Lakes and Roads in Hugo, Minnesota”.
After you have typed in your title, left click and hold over the title, and drag the mouse to reposition it.
Double left click on the title to display a properties dialog box similar to the one on the right. Here you can make other changes; for example “Change Symbol” is the button for increasing the text size or changing fonts. Experiment with the settings.
Return to the Insert Menu (as you did with the title) to add a North Arrow.
Select a north arrow design from the popup menu and then left click OK.
The north arrow is put on the page with a box around it. You may reposition it as with the title, and you may increase the size by dragging a corner.
Use the Insert Menu to add a Scale Bar. Detailed instructions aren’t provided, but the sequence is similar to adding a north arrow.
Add a Legend from the Insert Menu. This will open a Legend Wizard (figure at left).
Possible map layers are shown in a pane on the left, and those to be displayed are shown in a pane on the right. You move layers between the possible and displayed with the arrow boxes in between the two panes. Left click the Next button (lower right of the Legend Wizard) to accept the default values. As you add the legend you will be asked several questions about the number of columns, boxes, style, and other options.
Click Next to accept the defaults through the successive windows, and then Finish. The Legend appears on the page.
Finally use the Text option from the Insert Menu to add a text box with a descriptive title, your name, and the date.
To modify a text box, select by left clicking. A right click will bring up a menu; select Properties. Use Change Symbol to increase the font. Select OK and Apply and OK. Move the text to a logical place on the page.
Switch to the data view (click the map icon in the lower left of the data pane)
Left click on the layer name “Lakes” in the table of contents, and a dark blue box should appear. Right click on the blue box.
Left click on Properties in the drop-down menu (see right).
Select the tab labeled “General” and change the layer name from “Lakes” to “Hugo Lakes” and click OK.
Similarly, change the roads layer to “Hugo Roads”
Notice the layer names in the legend change “on the fly”, as you change them in the Table of Contents, they are changed on your layout.
You map should look something like the image below.
To complete this part of the assignment export the completed map to a .pdf formatted file.
Make sure you have selected Layout View, then left click on FileExportMap (see figure left below).
The steps below are shown in the video: Export Print
This will open an export window (right).
Typically, you restrict the output to the graphic extent (check box in the extreme lower left of the export window).
PDF files are often chosen when the map page is to be distributed. One of the graphic formats (e.g., .TIF, .JPG) is selected when the graphic is to be incorporated into another document.
Saving Your Project
Save the project, so that you may open it later, by using the main ArcMap menu window,
File Save. The steps below are shown in the video Saving Project
You’re usually best served when saving the map in the lesson directory that contains the associated data files, in this case, our L1 directory. The map is saved with the file extension .mxd.
Setting Relative Paths While Saving
ArcMap project files (saved with an .mxd extension) do not save any real data, but rather instructions on how to compose the map. This can present some problems when moving projects among computers, so we’ll now show you how to avoid some of these problems. The steps below are shown in the video RelativePaths.
First, create a new ArcMap project (save your old project first), then left click on the New Map button, shown at left.
Add the roads.shp layer from the L1 directory.
Right click on the name roads in the table of contents window, and left click on Properties at the bottom of the drop-down menu
Left click on the Source tab found near the upper right of the window, and look in the window about mid-way down. Note that there is a path, starting with a drive letter, shown below as “X:\courses\FR3131\LabData\L1\roads.shp.”
This path is the drive and sequence of subdirectories that lead to the displayed data file. Your path will be different, depending on the directory you are using to store and retrieve data, but the important point is that it contains a drive letter at the start, in this case, X:.
In this case the path is “hard-wired” to the data set, and the ArcMap project you’ve created knows to look there when you ask it to display this map.
Unfortunately, this storage arrangement isn’t very flexible, or portable. If you move your project files, including all data, to another computer, the drive letter or directory you save the data into will likely be different, for example, C:\ or D:\ instead of E. The path to the data will then be incorrect, and the data won’t be displayed.
If anything is different in the path, the project will not be able to locate and display the data. In the current state, the map project is difficult to move between computers.
Perhaps worse, even if you don’t move the data, but do something as simple as rename the directory, the map project won’t locate the data correctly.
This isn’t a problem if you always work on a computer with fixed drives, and you never change the subdirectories. But many folks want to move their data and projects around.
There is a fix, by specifying relative path names. To do this, left click on FileMap DocumentProperties (see right).
This will open a window with several blank fields for a map title, subject, keyword, and others.
Left click on the check box “Store relative pathnames to data sources”, near the bottom.
Left click on Apply, at the lower right of the window.
If you then save the map project in the same subdirectory as the data, you can easily move your project and all the data to a new computer by moving the entire subdirectory.
In this case, save your map project by File Save As and navigate to \L1 directory, naming your project appropriately, you should be able to move your projects/data among computers without problem. If you don’t do this, your project may open, the data listed, but with nothing showing in your data pane.
There are a couple of confusing aspects of saving maps. ArcGIS documentation sometimes refers to the files with an.mxd extension as map files, sometimes as project files, and sometimes as map project files. Just remember that when you see these three different names, they are often talking about the same thing, but sometimes not. Map project file is perhaps the clearest way to describe an .mxd file.
A second, more confusing aspect of map project files is that they do not contain any spatial data. This can cause problems if you are not careful.
For example, if I save the “map” I created above into the file “MyFirstMap.mxd” on a portable disk drive and move it to a different computer, opening MyFirstMap.mxd will show my data sets in a table of contents, but my data view and layout view will be empty.
This is because the file MyFirstMap.mxd doesn’t hold the data. It only holds the instructions on where to find the data, and what symbols to use when displaying the data, among other information. If I haven’t also moved my data to the new computer, then there will be nothing for the map project file to display.
Think of the .mxd file as the recipe, and the data as the ingredients. You need both to make a map. If you save the .mxd in the same directory as the data, then you can easily move both the .mxd map project and the data the same time.
You can avoid this problem by
1) making path names relative, and
2) saving the .mxd file in the same directory as the data, in this case, into \L1 directory.
You should follow this two-step process for all lessons, saving data onto your drive, and saving the .mxd with relative paths, into the same subdirectory as the data.
Manipulating Symbology
Remove the roads layer (right click on the name in the TOC, then left click on Remove), and add the layer “wet_land.shp” from the L1 subdirectory. This layer shows polygons that depict the wetlands of the Hugo USGS quadrangle, in Minnesota.