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Geography 387 Lab 1 Exploring ArcGIS Fall 2011

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Lab 1: Exploring ArcGIS

1. Purpose

To familiarize you with the following:

The main modules of ESRI's ArcGIS software Displaying data, searching data, and publishing data Navigating the ArcGIS help files Basic cartography Provide the background necessary for future lab exercises

2. Introduction and background

In this course, we will be working with ESRI's ArcGIS 10.x software. ArcGIS is widely used in

industry by professional GIS users. Since version 8.0, ArcGIS has been a Windows-based GIS

program -- a significant departure from the structure of versions 7.x and older, which used

command line interfaces in DOS or UNIX.

Working in ArcGIS typically uses three main modules: Catalog, ArcToolbox, and

ArcMap. These modules represent the three basic necessities of GIS: data management, data

analysis, and data output/mapping. In this lab we will cover these modules in greater depth, as

well as discover some of their key functionality.

Cartography In this lab we will also give some basic principles of cartography. This portion of the lab will

provide you with the basic guidelines and requirements for all maps handed in with lab

assignments. We will have a more in-depth lab on cartography in Lab 4.

Additional information Additional information on ArcGIS software can be found through the ArcGIS web site, and

through the ESRI Virtual Campus web site, which offers several free tutorials on ArcGIS and

ArcGIS extensions.

http://www.esri.com/software/arcgis/

http://campus.esri.com/


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3. Getting Started

Lab equipment

It is strongly recommended that you purchase a flash (pen, thumb) USB drive for storing your

lab materials and data.

Logging in

To log into the GIS Lab computers, you use your SSU Seawolf user name and password.

Creating a Work Directory

Keeping track of the files you use and create with the GIS tools is very important.

The GIS software will work most efficiently if you work with your data on the local hard

drive (C: drive). However, the lab computers are not a reliable place to leave files from one

week to the next. Files left on the lab computer MAY NOT be there when you return!

Therefore, keeping your data on a portable storage device of your own, such as a “flash

drive”, will make it necessary to copy data to the local drive of the computer you are using

and when you are done working, to copy the data back to your flash drive. Each computer in

the lab has a directory at C:\WorkSpace. You are strongly urged to use this directory and

create a temporary subdirectory in it each time you use a lab computer.

Double click on the My Computer icon, or go to Start -> Programs -> Windows Explorer or

push the window key on the keyboard then the "E" key (window key and "M" will minimize

everything if you get lost in multiple windows).

Open the C:\WorkSpace folder. Then right-click in the white space and select New ->

Folder. Always give your temporary folder a logical name. e.g., what you're working on, say

"jeff_lab1". The path to this folder is then "C:\Workspace\jeff_lab1\".

Note: To avoid problems in ArcGIS, DO NOT put spaces or punctuation in the names of

files, folders, feature datasets or feature classes. Use the "_" character instead to separate

parts of names.

Copying Data

You need to download the data for Lab 1 to your work directory. To get the data go to the class

website and download the data for Lab 1. Save the downloaded zipped data file to your work

directory in your flash drive, network drive, or a folder you created in C:\Workspace.

You need to unzip the file. Find the downloaded .zip file for lab1 in Windows Explorer. Double

click on lab1.zip and WinZip will open. Click the "Extract" button to extract the Zip archive


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contents to your work directory. After you successfully extract the files you can close WinZip.

Then in My Computer open the "lab1" folder to verify that the files and folders have been

extracted.

The data that we will be using in this lab are:

Geodatabases:

cotati_rohnert_park.mdb – a file geodatabase containing Cotati and Rohnert Park streets,

land parcels, city limits, and schools

usa_geog – a file geodatabase containing state boundaries of the lower 48 states

Shapefiles:

uscnty - Shapefile of the counties in the lower 48 states

usriv - Shapefile of rivers in the lower 48 states

usroad - Shapefile of roads in the lower 48 states

Maps:

school_map.mxd - ArcMap document file displaying the schools of Cotati and Rohnert

Park. This map uses the features found in the cotati_rohnert_park geodatabase.

Turning in Lab exercises

There is no capability in the lab for printing. All lab exercises – maps, Word and other

documents – will be turned in electronically as email attachments to your lab instructor.

As your work through this lab, this document has questions in gray boxes. You need to create a

new Word document to contain your answers, and when you are done, email the Word document

to the lab instructor for your section.

4. About ArcGIS

Introduction to ArcMap

ArcMap is the central module of ArcGIS used for displaying, organizing, browsing, managing

and processing your data and working with map documents. The other two main modules,

ArcCatalog and ArcToolbox are accessible from within the ArcMap application.

Starting ArcMap

Now we will start ArcMap and explore its contents. To start ArcMap, click on the Start

button and navigate to All Programs -> ArcGIS -> ArcMap 10.


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What is in ArcMap?

When ArcMap starts, it asks you what map document you want to create or work with.

At this point, just click on OK, to have ArcMap start with a blank map document. Your ArcMap

application will look very much like this:


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ArcMap looks similar to many Windows applications. There is a menu across the top of the

window – with items such as “File”, “Edit”, “View”, and “Help”. Under the menu, there are one

or more rows of small icons representing convenient shortcuts to often used actions. On the left

side of the application is a window with the subtitle “Table Of Contents”. The large window in

the rest of the application is the map area (it has no subtitle) and is where the map data are

displayed. On the right edge of the window are two small sideways icons, one says “Catalog”

and the other says “Search”.

By moving the mouse cursor over an icon along the top and letting it rest there without clicking,

the application will pop up a brief hint of what action that icon performs when clicked.

Question 1:

What is the action of each of the following icons?

a.

b.

c.

d.

e.

f.


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Browsing for data

Without clicking, move the mouse cursor over the “Catalog” icon on the right edge of the

application window. A window will appear with the subtitle “Catalog”:

Without clicking anywhere, move the mouse cursor around inside the Catalog window – notice

that the window remains visible. Now, still without clicking anywhere, move the mouse cursor

outside the Catalog window for a second or two – notice that the Catalog window disappears.

Experiment with this behavior and the “Search” window icon. Notice which window pops open

and when it disappears.

Now, hover the cursor over the “Catalog” icon and wait for the Catalog window to pop open.

This time, while keeping the cursor in the Catalog window, click on the small ‘thumb-tack’ icon

that is in the upper-right corner of the Catalog window: . The thumb-tack turns to point

downwards: . Now, move the mouse cursor outside the Catalog window and notice that the

Catalog window does not disappear.

The Catalog is the primary means of browsing data that is available for use in ArcGIS.

ArcCatalog shows data in a structure that is somewhat similar to the way Windows Explorer

shows files on the computer. Data is organized into a hierarchy of folders and subfolders. It is

possible to expand and collapse the display to show various levels of depth into the folder

hierarchy. The small plus and minus signs to the left of each folder allow control of whether

data inside the folder is listed. Experiment with clicking on the and symbols to see how

this works. Since there is little data at this point, there isn’t much to see. But you can see names


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of containers that are suggestive of the power of Catalog, for example: “database servers” and

“GIS servers”.

5. Connecting to your lab data

Now, let’s get the data for lab 1 visible in the Catalog.

Catalog will only look for data in places where you have told it to look. Earlier in this lab, you

downloaded and unzipped the data for lab1. It was suggested that you create a folder for the data

for this lab, e.g. “C:\Workspace\jeff_lab1”. You need to tell Catalog to look for the data in that

work folder. This is done with a “folder connection”.

Click on the folder connection icon and navigate to the folder where the data for lab1 has been

unzipped. In this document, the example will be “C:\Workspace\jeff_lab1”.

Click “OK”.

Then look in the Catalog window in ArcMap again. You will see a new entry under “Folder

Connections”. Expand the directories under this connection and you will see all the data for this

lab 1:

Question 2:

Which of these icons creates a “folder connection”? Write the letter in your answer. (hint: hover)

A.

B.

C.

D.

E.

F

s


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You can see the file geodatabase for cotati_rohnertpark with features for city_limits, parcels,

schools and streets. You can see the usa_geog file geodatabase that has states_line, states_poly

and states_zzzzzz. There is also, in the jeff_lab1 directory, a map document called “school_map”.

Under the map document are listed four shapefiles: uscnty, usriv, usroad and zzzzzz.

6. ArcGIS manages GIS data

It is important to understand that ArcGIS manages geographic data in ways that Windows does

not understand. To demonstrate this, open up Windows Explorer and navigate to the

C:\Workspace\jeff_lab1 directory. Then arrange the window for ArcMap so that it is on the right

side of the screen and arrange the Windows Explorer window so that it is on the left side of the

screen. Have the Windows Explorer window overlap the ArcMap window somewhat, so that you

can see both the files that Windows Explorer shows in C:\Workspace\jeff_lab1 and the GIS data

that ArcMap is showing in the Catalog window. Like this:


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There are important observations to note:

- The Catalog window of ArcMap shows 1 feature named “uscnty”. The Windows

Explorer window shows 7 files of various types that have “uscnty” as their root

name. All 7 files in Windows comprise the single GIS feature in ArcMap.

- Windows thinks that one of the files for “uscnty” is an Adobe Illustrator file. It is

not an Adobe Illustrator file.

- None of the icons that Windows Explorer uses for the files match the icon used by

ArcMap for that feature.

- Windows also shows two files named “uscnty.shp”, but with different icons and

types: one is listed as a “SHP file” and the other is listed as a “XML Document”

file. These are not two copies of the same file.

- The Catalog window shows a file geodatabase called “usa_geog”. The Windows

Explorer window shows a folder called “usa_geog.gdb”. ArcGIS implements a

file geodatabase as a directory folder.

Now, in the left panel of Windows Explorer, click on the “usa_geog.gdb” folder and look in the

right panel of Windows Explorer and note the list of files contained in that folder.


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Note the following:

- None of the files that Windows Explorer shows as contained in the usa_geog.gdb

directory contain names that have anything about “states_line”, “states_poly” or

“states_zzzzzz” in them. ArcGIS creates all these files seen in Windows Explorer

and manages their names and contents. All these files, together in the directory,

are understood and managed by ArcGIS to represent the file geodatabase and the

3 geographic data features contained in it.

Demonstration 1: in ArcMap, in the Catalog window, right click on states_zzzzzz in the usa_geog

file geodatabase and then left click on “Delete”. ArcMap will ask you to confirm the deletion of

the feature. Click “Yes”. Now, go to the Windows Explorer window where the contents of the

usa_geog.gdb directory are shown. Note that the filenames are unchanged but that several of

them have updated modification times. ArcGIS has removed the states_zzzzzz feature from the

geodatabase by modifying several files in the usa_geog.gdb directory.

Demonstration 2: As a final example showing how ArcGIS manages its files, go to the Windows

Explorer window, click on the directory containing the lab files (in this case,


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“C:\Workspace\jeff_lab1”), so that Windows Explorer shows the files in that directory. You

should see the various files for uscnty, usriv, usroad and zzzzzz shapefiles. In the Catalog

window of ArcMap, right click on the zzzzzz shapefile (just under usroad) and left click on

“Delete”, then click “Yes” to confirm that you want this shapefile deleted. Now look in the

Windows Explorer window and notice that all 7 files for the “zzzzzz” feature are gone. ArcGIS

has deleted them.

It is important to allow ArcGIS to manage the files necessary for geographic data and to do your

GIS data management tasks in ArcGIS, not in Windows Explorer!

7. Catalog

Returning our attention to the Catalog window in ArcMap, we can use the Catalog window to

browse the GIS data for this lab.

Looking at the list of GIS data in the Catalog “tree”, there are icons used with each entry that

indicate the type of GIS data. When Catalog is initiated, it automatically looks in connected

folders for spatial data. Any spatial data it finds will be shown with a special icon to indicate the

type of data in the file or folder. In particular, four basic spatial types are: points, lines, polygons,

and rasters. ArcGIS uses these icons with these four types:

Point

Line

Polygon

Raster

Question 3:

If you use Windows Explorer to copy files into the folder directory of a file geodatabase, does

ArcGIS show those files as GIS data in that geodatabase?


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Previewing data

You can see what these data types look like using the Preview capability in the Catalog. To do

this, right click on “city_limits” and then left click on “Item Description…”. This opens a

window that shows some information about the city_limits feature class:

There are two tabs at the top of this window, one for “Description” and the other for “Preview”.

The tab for Description shows the name of the feature, with a “thumbnail” representation of the

data, followed by text that gives information about the data. This “data about the data” is called

“metadata”. Scroll through the window to read the rest of the metadata about city_limits. In this

case, you could reasonably conclude that there is not much useful metadata about this feature.

Click on the “Preview” tab. This changes the Item Description to a view of the data in

geographic form. In this case, you see the two polygons that represent the boundaries of Cotati

and Rohnert Park. You can see the relative sizes of the two towns and get a general idea of the

shape of their boundaries.

Notice that in the Preview window, under the tab for Preview is another toolbar with a drop-

down list showing “Geography” and them some icons to the right of that. You can hover over the

icons to find out what they do. You can experiment with them briefly to see how they work.


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Click on “Geography” in the drop-down list and select “Table”. This switches the window to a

list of the attributes that are associated with each polygon. In this case, there are attributes for

two polygons.

Also notice that near the bottom of the window there is now a scrollbar that allows you to scroll

right and left so you can see all the attributes for the data. Scroll to the right and look at the rest

of the attribute data for this feature.

Feature attributes are organized as a table of columns and rows, much like a simple database or

spreadsheet. Each row of the table corresponds to a part of the feature. In this case, there is one

row for Cotati and a second row for Rohnert Park. Each column of the table corresponds to a

field of information about every row. In this example, there is a column for the full name of the

city – this field is called “FULL_NAME”, and there is a column for the regular name of the city

– this field is called “CITY_NAME”.

There are other fields in the attributes for this feature: “OBJECTID”, “Shape*”, “Shape_Length”

and “Shape_Area”. Each record (i.e. row) of the table has a value for those fields as well,

although what they mean is probably not clear at this point.

Click on “Table” in the drop-down list and select “Geography” again. It is possible to leave the

Item Description window open and click on other features in the Catalog window and have them

appear in the Item Description window.

Leaving the Item Description window open, click on “parcels” in the cotati_rohnertpark

geodatabase. The preview shows the shape of the feature for land parcels for Cotati and Rohnert

Park. You can, again, use the icons at the top of the preview panel to explore this feature. If you

switch to “Table” preview, you will discover that there are over 14,000 records for this feature. If

you look at the bottom of the Item Description you will see that there are 14,044 parcel records.

You can scroll left and right as well as up and down to see the records. You will also see that

there are different attribute fields (in the columns) for this feature than for city_limits. The

meaning of these fields is not apparent.


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Continue to preview other features in the lab data. Use the Description and Preview tabs of the

Item Description window, as well as the Geography and Table previews to explore the other

features in this lab.

Finding data in Catalog

When previewing tabular data in Catalog, it is possible to search for data in the table. To do

this, open to the table view, and click on the Table Options button in the lower left

corner of the Item Description window. Then select Find & Replace… This will open the

Find and Replace window that has two tabs: one for “Find” and one for “Replace”. For

now, just use the “Find” tab.

In the “Find what” field you can type in a text string to search for. You can set the “Search”

drop-down list to search down the attribute list, up the attribute list, or search the entire

attribute list.

Once the first match has been found, you can look for further matches by clicking on the

'Find Next' button.

Question 4:

As a new user of the parcel feature data for Cotati and Rohnert Park, can you think of a convenient

place you might look to find the meaning of fields like “APN”, “LEVEL_”, “RANK”, “ADJUST”? (Hint: it

does not involve leaving your desk or searching the internet.)

Question 5 (two parts):

Which feature class seems to have the most metadata?

What company is credited with working on that feature?


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In addition to the Item Description of a feature, you can also see the Properties of a feature. In

the Catalog window, right click on city_limits and select “Properties…” A Properties window

shows several tabs, each tab showing various sets of properties about the feature. Unlike the Item

Description window, you have to close the Properties window each time you want to look at the

properties of a different feature. Explore the properties of the various feature data in this lab.

Notice how some features have more tabs in their Property windows than others.

8. ArcToolbox

Introduction to ArcToolbox

ArcToolbox is the ArcGIS module used for data processing, analysis, and conversion. It contains

a large set of tools that allow for specialized operations, or “geoprocessing” tasks. ArcToolbox

also provides a means for the user to write scripts and create customized tools for a particular

need.

Starting ArcToolbox

To start ArcToolbox, click on the ArcToolbox icon in the toolbar near the top of ArcMap.

Question 6:

Using the uscnty shapefile, find the state or states to which the following counties belong. Note

that there may be more than one state with a county of that name.

County State(s)

Pend Oreille

Adair

Switzerland

Question 7:

What is the name of the XY Coordinate System of the schools feature class in the cotati_rohnertpark

geodatabase?


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Like Catalog, ArcToolbox is one of the major ArcGIS modules, and is "embedded" in the ArcMap

application. Usually, when it first appears, it pops up as a ‘floating’ window:

The ArcToolbox window can be controlled just like the Catalog window – it just has to be

‘docked’ first. To do this, start dragging the ArcToolbox window by its title bar. As soon as you

start dragging it, ArcMap will show blue ‘docking indicators’ to show where the ArcToolbox

window can be docked. Without releasing the mouse button and continuing to drag the

ArcToolbox window by its title bar, drag your mouse cursor over to the far right center docking

indicator. When your mouse is over the indicator, ArcMap will show a large blue rectangle

showing where the docked ArcToolbox window will snap in place. Release the mouse button

and the ArcToolbox window will be docked. It now will have the ‘thumb tack’ icon in the upper

right corner which functions just like the thumb-tack control for the Catalog window.

ArcToolbox is organized in a fashion similar to the catalog tree in Catalog. By clicking on the

‘+’ next to a tool heading (Data Management Tools, Analysis Tools, etc.) you can view the tools

available under that heading. Some toolboxes have ‘sub-toolboxes’ called “toolsets”. Within

toolboxes or toolsets you’ll see different kinds of icons for tools:

A toolbox

A toolset

A model builder tool

A hard-coded tool

A script-based tool


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For model builder tools, hard-coded tools and script-based tools, you can right click on the tool

and then select “Help” to have ArcMap open a window with a description of what the tool does

and how it works.

To run a tool, simply double-click on the specific tool you want to use. This will open a dialog

box that allows you to set the various inputs and outputs and other options related to the tool.

Take a few minutes to explore the Toolbox and get a sense of what kinds of tools are available.

9. Map documents

So far, you’ve been looking at Catalog and ArcToolbox, without really using the central window

of ArcMap. Now it’s time to see a map!

Let’s open the school_map map document. Do this by clicking on the “Open” icon in the top

toolbar (or selecting File->Open from the menu bar) and navigating to the school_map document

in the lab data. OR… just drag the school_map document from the Catalog window into the

center panel of the ArcMap window.

Question 8:

Use the ArcToolbox window to find and examine the "Overlay" toolset. List the names of the tools in

this toolset.


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The map looks like this:

You will notice that map in the school_map document is not particularly stunning from a

cartographic standpoint. Later in the lab, you will modify the map to make it a bit more

cartographically pleasing.

The Table of Contents

Now that you have a map document open, you can see that there are items displayed in the Table

of Contents window on the left. The Table of Contents shows a tree display of the layers (the

"layer tree") in the map (and whether or not they are currently displayed). Note a couple things

about the Table of Contents (ToC) window:

- The window has the ‘thumb-tack’ icon. Just like the Catalog and ArcToolbox

windows, the ToC window can be docked, undocked, tacked or untacked, or

closed. No matter where you dock the ToC, the map is still displayed. If you close

the ToC, you can open it with the icon at the top of the ArcMap window.

- There is a set of icons under the title bar of the ToC window that switch the way

the layers in the map are shown: These icons show these views of the

ToC:


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Shows the layers (i.e., feature classes)

by their names and a checkbox for each

layer to indicate if it is drawn (i.e.

visible) in the map.

Shows information about the location of

the data for each layer.

Shows which layers are visible, and

which layers are selectable.

Shows which layers are selectable and

how many features of each layer are

currently selected.

Sets a few options for how the ToC is

displayed.

Layout vs. Data view

The central window of ArcMap provides a view of the data. In the lower left corner of this

window is a tiny toolbar with 4 icons. You can hover over these icons to find out what they do.

From left to right, these 4 icons are:

- “data view” This draws the map with just the data feature layers. The map is not

drawn with the other ‘non-feature’ map elements such as legends, scale bars,

north arrows, titles, etc. A lot of GIS work is done in the “data view”.

- “layout view” This draws the map as it is placed on paper for printing. It does

include the additional non-feature map elements such as north arrows, legends,

scale bars, etc. that would appear on a printed version of a map. The layout view

is pretty much a “what you see is what you get” presentation of the printed map. It

shows the edges of the page and where on the page the elements of the printed

map will appear.

- “refresh” This forces ArcMap to redraw the map – in either data view or layout

view.

- “pause/resume” This controls whether ArcMap draws the map at all. Usually,

ArcMap is able to keep up with you as you modify data and change the way it is

drawn. However, sometimes waiting for the map to redraw can interfere with

getting work done and it can be convenient to tell ArcMap to stop drawing the

map. Then when you are done working, you can have ArcMap resume drawing

the map.


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Important observation to make:

Layout view has its own set of controls for zooming in and out and panning around the

page on which the map is drawn. These controls work differently than the controls for

zooming in and out and panning around the map in the Data view. As you switch

between Layout view and Data view, notice the set of toolbar icons near the upper-left of

the ArcMap window that are grayed-out when in Data view and are only active in Layout

view.

The tools for zoom and pan (and other actions) in Data View are:

The tools for zoom and pan (and other actions) in Layout View are:

Explore the difference in zooming in and out and panning the drawing using the above tools.

Making a map layout for cartographic output

After exploring, go to the Layout view. You can do this by either clicking on the Layout view

icon at the bottom of the view window, or by selecting View-> Layout View from the menu.

In Layout view, you can insert a title, legend, neatline, etc. on your map. Click on Insert in the

ArcMap menu and select the object that you would like to add. Experiment with adding

information to the school_map. Try adding a title, legend, scalebar, north arrow, and your

name. Do not save your changes. You can delete any of the objects you added by using the

“Select Elements” tool (find it in the toolbar yourself), then selecting and element by clicking on

it (it will show selected by a selection box around it) and then pressing the "Del" key. You will

make this map more appealing later in the lab. For now, do not save your changes.

Creating your own map

Now that we have spent some time with a created map, let's make our own. In ArcMap, you

cannot have two map documents (.mxd extension on filename) open at the same time, so to open

a new map document, we either need to open a new ArcMap window or close the existing map

document. Since we will not need to use the school_map document for this portion of the lab,

click on File -> New (or you can use the shortcut key "Ctrl-N" or click on the new file button on

the toolbar), and select "Blank Map" in My Templates. Do not save changes to the

school_map.mxd map document.


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To add data to a map document, there are several options:

1. Use the "Add data" icon in the ArcMap toolbar

2. Navigate to File -> Add data

3. Drag and drop data from the Catalog window. With the Catalog window open, drag each of

the uscnty, usroad, usriv and states_poly features into the main ArcMap window. (Dragging is

done by: move the mouse cursor over the name, hold the left mouse button down, drag the data

straight from Catalog to the map window in ArcMap. Release the mouse button. The data is

‘dropped’ into ArcMap.)

Relative Paths

Since it is likely that you will open data from both your USB drive and from copies on the local

lab computer drive, it is helpful to use a “relative path” to your data. This will be handy if you

copy your lab data folder to a local drive to work, or if you move it from one drive to another. If

you do not store your data sources as relative path names, you will run into the problem of

ArcMap looking for the data on the last drive which you used. For example suppose you create a

map document with your data located in C:\Workcpace\jeff_lab1 and you then copy the entire

folder to another drive (or another directory). When you open the map document from the new

folder, it will still look for the data in C:\Workspace\jeff_lab1. Using relative path names tells

ArcMap to look for the data in the same relative location to the map document (e.g., in the same

data folder, e.g., jeff_lab1, or wherever it is in relation to the map document).

To set your map document to use relative path names, click on File -> Map Document

Properties, and put a check in the box next to "Store relative path names to data sources" Click

OK. Note: You will probably want to do this with ALL map documents that you create in this

course.


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Drawing order

If you look at the Table of Contents window, you should see the names of the four layers you

added to the map, along with a sample of how the data in each layer is represented in the map.

Roads and rivers are lines that are drawn in a color and width. States and counties are polygons

that are drawn with a border color and a fill color.

The usual default for the Table of Contents is to show the layers in the order they are drawn, with

the bottom layer drawn first and the top layer drawn last. Usually, ArcMap decides for you that

polygon features are drawn before line features and that line features are drawn before point

features. But you can override this.

Using the mouse, you can drag the items in the ToC up and down to change the order they are

drawn. Try this. Put the mouse cursor over the layer named states_poly and drag it up and down

in the ToC. You’ll see a horizontal black line follow you along as ArcMap indicates where that

feature will be dropped if you release the mouse button. Drag the states_poly layer to the top of

the ToC. Notice how drawing the state polygons on top hides the the layers below it – the rivers,

roads and counties. Now, drag the usriv layer to the top of the ToC. Now, the rivers are drawn on

top of the states, but you still can’t see the counties or the roads.

You can also “turn off” a layer by clicking on the little checkbox next to its name in the ToC.

You can turn the layer back on by clicking in the empty box and the checkmark is added and the

layer is now drawn. Whether a layer is drawn or not is called “visibility”. If a layer is

‘underneath’ a visible layer that covers it completely, turning the visibility of the underneath

layer off and on doesn’t have much effect on the appearance of the map.

Experiment with different orderings of the ToC and turning layers off and on to see how drawing

order and visibility changes the appearance of the map. When you are done, arrange the layers in

the ToC so that the counties are on the bottom, followed by states, followed by rivers, with roads

on the top. Mark all layers visible.

Occasionally, even if you set the map document to use relative path names, you will still have problems with "broken sources." These will be indicated by a red ! next to the layer's name.

To fix this problem, go to Properties -> Source ,and re-set the appropriate data source by clicking on the "Set Data Source" button.


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Symbology and data appearance

Layer properties: In ArcMap, to view the properties of a data layer, double-click on the layer's

name in the ToC. (Or: right click on the layer’s name and select “Properties”.) This will take

you to that layer’s properties window. Note: The ArcMap Layer Properties window will provide

different information than was found in the Properties window called up from the Catalog

window. You can try this yourself, now, to see.

From the properties window you can view and modify the display properties of a layer, including

the layer's transparency, labeling options, symbology, and source. This lab will only cover a few

of the options (display, symbology, and labels), but you will want to take a few moments to

familiarize yourself with the other functions in the properties window.

Symbology: Under the symbology tab are the options for changing the display of data. From

here you can decide how the features of that layer are drawn. On the left side of the Symbology

tab is a list you can select for how to show the features in that layer:

- Features: use one way of drawing all features in the layer

- Categories: draw each feature of the layer in a way that depends on some

categorical attribute of the feature

- Quantities: draw each feature of the layer in a way that depends on some

quantitative attribute of the feature

- Charts: draw a pie chart or bar chart with the feature to show some quantitative

attribute(s) of the feature

- Multiple attributes: draw each feature of the layer in a way that depends on a

combination of categorical or quantitative attributes

For example, if you want to use usroad to display type of road rather than simply location, open

the Properties window for usroad, and click on the Symbology tab. As the default, usroad is

drawn as a single symbol (i.e. all roads are drawn the same way).

Instead, we’ll show the different values of the ADMN_CLASS attribute for the roads. We will

use Categories -> Unique values.

Question 9:

Zoom way in to the San Francisco bay area with both the states_poly and uscnty layers

visible. What do you notice about the edges of the polygons between the two layers? What

might cause this?


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Under the Value Field drop-down list, select ADMN_CLASS. You then tell ArcMap to scan all

the features in the layer to find all the existing values of the ADMN_CLASS attribute. To do

this, click on the “Add All Values” button. Then click on “OK” to apply the symbolization and

dismiss the Properties window. The map is redrawn (from the bottom up) with the new

symbolization of the roads layer.

To change the symbology of other layers, the process is the same. Experiment with the other

layers to see ways in which line and polygon features can be symbolized.

Notice how the ToC shows the symbolization of each layer that is currently in effect in the map.

Symbology and data appearance (Cont.)

To change the representation of Interstate, State Highway, and US Highway, double click on the

line next to the name and select an appropriate line symbol from the Symbol Selector. Change to

appropriate symbols. Since there are no "other values," you can deselect the <all other values>

symbol. When the display is to your liking, click OK.

Display

A useful feature on the Display tab of the Layer Properties is the option to set transparency. This

allows for a layer to be seen through another layer. For instance, with the states_poly layer

displayed will a fill color, the uscnty layer cannot be seen. By setting the top layer to some level

of transparency, both layers can be seen.

To explore this, we'll make the states_poly layer partly transparent. Open the properties window

for states_poly and select the Display tab. In the field next to “Transparent:” enter 50 and click

Question 10:

How many different named river systems are there? What are their names?


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on OK. Now the state boundaries are shown clearly, and the county boundaries are less

pronounced in the display.

Labels

Using the Labels tab under properties is an easy way of drawing the names of features on a

map. We will try this with the usriv layer and add labels for river names. Go to the Labels tab in

the usriv property window. To insert labels, check the “Label features in the layer” box and

select which field to use for labeling (we will use "Name"). From here you can change the style,

symbol, font, font size, and location of the labels by selecting from the button options under

"Label" in the window. Take a few minutes to explore these options.

Data Query

From the Catalog window, you could find text strings in attribute tables. This was done earlier in

this lab. ArcMap provides significantly more options for querying data. Let's explore these

options using the attribute table for the counties.

Right-click on the uscnty layer,and select "Open Attribute Table." This will open a new, floating

window containing the attributes of this feature. Like the Catalog, ArcToolbox and ToC

windows, the Table window can be docked, tacked-down, or hidden.

In the top of the Table window is a row of icons.

By clicking on the leftmost icon, a menu pops up that has many operations you can do with the

attribute table.


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Some of the functions explained:

Find & Replace - to find text strings in the attribute table and/or replace them with another string.

This is the same function that was used from the Catalog window earlier in this lab.

Select By Attributes / Switch Selection / Select All / etc. - allows for writing a query to select

records matching the criteria specified in a structured query, allows for changing of the selection.

Add Field - allows for fields (attributes) to be added to the feature

Related Tables - lists which tables are connected as "Related tables"

Create Graph / Add table to layout - options for displaying the attribute table data in the map

Reload Cache - Re-loads the table, in case of changes

Export - Exports the table as a file, offering various formats.

Appearance - Changes the way in which the table is viewed (i.e., selected record highlight color)


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(VERY) Basic principles of cartography

Cartographic Guidelines (courtesy of David Jones, UCSB)

1. Data in maps: A. The data should take up a majority of the area. You should avoid excess white space.

B. Inclusion of unnecessary data should be avoided - most often simple is better.

C. Bright, flashy colors such as red should not be used unless you specifically need to do so.

2. Titles: A. Should usually be in upper case.

B. Should not be sentences, but should be simple and to the point.

C. Should not be the focal point of your map.

D. Should almost always be black or dark text.

E. Should be placed in a location on the map so as to not obstruct any other portion of the

map.

3. Scalebars: A. NEVER have a scale bar that extends all the way across a page. Scalebars should not be

the focal point of the map as they are for reference only.

B. Scalebars should use appropriate measurement systems. Example: km for Sonoma

County, meters for SSU campus.

C. Avoid using English measurements on maps (miles, feet, yards). Metric is more

compatible with the rest of the world.

D. Use intervals that make sense. Units of 2,5,10, 20 are common. For example, do not use

23.4.

4. Borders: A. Maps need borders, they should usually be black.

B. Borders are known as "neatlines."

C. Neatlines should be a large enough width to be clearly seen from a distance.

5. North Arrows: A. North Arrows should be unobtrusive.

B. North Arrows are not always needed. If mapping a state (or other large, well known

area), a arrow is not needed, because we can usually expect people to know which way is

North.

6. Legends: A. Legends should be unobtrusive

B. Legends should only show defined features that are not obvious. For example black

points are usually associated with landmarks such as cities. You can assume that people

understand this.


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C. Legends do not need a heading 'Legend' or 'Key'.

7. Text on Map: A. Text should NEVER cross other text or other features of the SAME color.

B. Labels for natural features such as streams, lakes etc. should be written in italics

C. Text should be readable!

8. Name on Map: There should be a name and date on the map. This information should go underneath the

neatline on the bottom right side, or below the legend.

9. WHITE SPACE: Do not waste space. Try to find the balance between too much white space, and cluttered

data.

10. Making maps for labs

For lab exercises, maps will be turned is as electronic documents, not printed pieces of paper.

Also, since map documents (.mxd files) do not contain the data they are mapping, you cannot

turn in the map document’s .mxd file. Instead, make a PDF document from the map and send the

PDF version in for your labs.

To make a PDF from a map, click on File Export from the ArcMap menu. Then set the “Save

as Type” to “PDF” and set the “Resolution” to 150. (300 dpi makes files that are very large!

They may not email successfully.)

Your maps for Lab 1:

Map 1

Using the states_poly, uscnty, usriv, and usroad features, zoom to your favorite state and make

a map of it in the Layout view of ArcMap. Follow the above listed principles of

cartography. Include whatever features (rivers, roads, counties) you feel are necessary (at least

one must be included). Turn in this map with your lab answer sheet.

Map 2 Using the cartographic guidelines listed above, correct the cartographic errors in

school_map map layout and turn in the resulting map.

11. Conclusion

In this lab, the basic functions of ArcGIS's Catalog, ArcToolbox, and ArcMap have been

covered. Hopefully you will now have a feel for navigating around the software and the lab

computers. If not, the best way to become comfortable is to keep at it. Spend as much time as

possible working with the software and with the computers!


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ArcGIS is a very large and complex application. As with any such software, the basics covered

in this lab do not come close to being comprehensive. To really grasp the software, you will need

to spend quite a bit of time just exploring, trying out different functions, seeing what works (and

what doesn’t), and just clicking on buttons, menus, bits of data, and especially the help files.

In the remaining labs this semester, we will spend time examining more specific ArcGIS

functions.

12. To turn in

The question sheet, with typed answers

Map 1: a map of your favorite state

Map 2: a corrected school_map layout

Submit electronic files via email to your instructor, with the subject "G387, Lab 1, [your

last name]".

Credits: The original version of this lab module was developed by the Department of Geography

at UC Santa Barbara. Used with permission. The original UCSB lab was tailored for instruction

at Sonoma State University by Matthew Clark and expanded for ArcGIS 10 by George Riner,

Center for Interdisciplinary Geospatial Analysis (CIGA).

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