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Lab Exercise |
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The goal of this exercise
is to give you a brief introduction to ArcView and its capabilities. You will
examine ArcView by looking at two different ArcView projects. The first project will help you to
understand some of the important features of ArcView while the second project
will introduce you to some of the different data types used in ArcView and to
the ways in which this data is represented. As
this lab progresses, you will find a number of Tasks that need to be
completed. At the end of the lab you
will be expected to submit a brief report that shows that you have completed
the set Tasks and that outlines any particular issues or difficulties that
may have arisen during the lab. Because
ArcView introduces some concepts and terms that you may not have met before,
a Glossary of Terms (some of which are specific to ArcView) will also be
distributed with this lab. All words
that are bolded and underlined in this handout have been included in this Glossary
of Terms. |
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Part A.
Project 1
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When using the UNIX
operating system, type arcview at the system prompt. In the Welcome to ArcView
GIS dialog, click Cancel. |
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At the top of the ArcView
window is a menu bar with four pull-down menus: File,
Project, Window, and Help. These menus are available when the Project
window (the smaller "Untitled" window within the ArcView window)
is active. Below the menu bar is the button bar with two
buttons, Save and Help. Below the button bar is the toolbar.
It doesn't contain any tools yet. The function of each
button and tool is displayed in the status bar at the bottom of the ArcView
window. Click on Help in the menu
bar and explore the help options. The
Help system, like ArcView itself, conforms to the Windows 95/98 look and
feel. Next, open the File menu
and select Open Project. |
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Navigate to the /home/u2/oc3902/lab0/introav/basics/lesson01
folder. Select l01_ex1.apr
(the project for Exercise 1 of Lesson 1) from the left scrolling list and
click OK. Note: ArcView projects always have an .apr
extension. |
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Currently, the Views icon
is highlighted. The New, Open, and Print buttons at the top of the Project
window let you create new views, open existing views, and print a view that's
highlighted in the list. As you click down the
icons on the left hand side of this window, you will see that this project
not only has two Views (Gross National Product and Population
Density), but that it also has a Table (Countries by Population
Density), a Chart (Birth/Death Comparison), and a Layout
(Population Growth Rates). It doesn’t
have any Scripts. These icons are also known as documents. Thus any one project may have a number of
associated documents. NOTE: The menu bar, button bar and toolbar all
change according to the document that is open. Each document type has its own menus, buttons and tools. When you click on the
View button, on the right side of the window, you see the names of the two
views currently contained in this project. You want to work with both views
at the same time so you need to highlight both of them. Hold down the Shift key and click on the Population Density view. Now both views in the list are highlighted. NOTE: This is a non-standard convention for multiple file selection. |
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Next, open both views by
clicking the Open button at the top of the Project window. The two view windows open
and ArcView's interface (menus, buttons, and tools) changes to reflect the
view document type. You can tell that the Population Density view is active
because its title bar is highlighted and its window is in the foreground. Move the cursor over the
buttons and stop on each for a few seconds.
Notice that a description of each is given in the status bar at the
bottom of the page. |
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Each theme
in the Population Density view has a title and information that describes
what the theme shapes represent. The World Cities theme represents cities of
the world. The Countries by Population Density theme shows countries. (Notice
that some of the countries display in yellow. This indicates that they've
been selected as a separate group.) In the background is a theme showing a
grid of latitude and longitude. Click on the Gross
National Product title bar. It becomes the active view. Again you see a theme of
world cities, a theme of countries, and a theme of latitude and longitude;
however, in this view, the countries are shown according to their gross
national product (GNP). You can
switch the display of a theme on and off by merely clicking on the check box
next to their names. |
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Each of these views
displays the world differently. In ArcView, you can display the same source data
differently by changing the properties of the views. To use a different
projection, for example, go to the Menu Bar and click on View, and then on
Properties. Within the Properties
box, go to the bottom left and click on Projection. Once you have selected your projection you will need to click
OK both in the Properties box and the View box before it is applied. Task 1: Select a Mercator Projection. What parts of the world are the most
distorted with this projection? Now
change to a Hammer-Aitoff Projection.
In broad terms compare the display of the world with the Robinson
Projection that was used initially. Close the Gross National
Product view by clicking on the icon in the upper left corner of the Gross
National Product window and choose Close from the menu. The view window
closes. |
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Now you'll look at the
attributes that are linked to the features in the Countries by Population
Density theme. Notice that the gray area
containing the name and the symbols for the Countries by Population Density
theme appears raised, indicating that this theme is active. Open the table for the
active theme by clicking the Open Theme Table button Use the scroll bar at the
right of the table and scroll down until you have seen all the selected
records (highlighted in yellow). You may want to widen the table window to
see the fields better. These correspond to the
countries highlighted in yellow in the View. Notice that there is also a Select None button that allows you
to unselect all the highlighted records.
Once used, however, there is no undo function to help you recover the
previous selection. Task 2: Scroll through the table and write out a list of the countries that have been highlighted in yellow. |
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Examine the other attributes |
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View the rest of the theme's
attributes by scrolling to the right in the table. Notice that the table
contains attribute information on growth rate and the total population for
1980 (Grw_rate80; Tot_pop80) for each country, as well as a range of other
data. Task 3: Find New Zealand.
What was its projected population for 2000 (Pr_pop2000)? Close the Table by clicking on the icon in the upper left hand corner and then clicking Close. |
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Next, you will open a
chart showing the birth and death rates for the highlighted African
countries. Click on the Project
window title bar (i.e., the window headed le01_ex1.apr) to make it active. Click on the Charts icon.
The Birth/Death Comparison chart is highlighted in the list. Click the Open button. The Birth/Death
Comparison chart is now the active document, and ArcView's Graphical
User Interface changes to display the menus, buttons, and tools you
use to work with charts. |
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The chart is covering up
the Project window, so close the chart.
Now make the Project window active by clicking on the area containing
the letters le01_ex1.apr. Next, click on the
Layouts icon to display the list of layouts in the project. NOTE: A Layout allows you to integrate documents
(views, tables and charts) and other graphical elements into a single window
to create presentation quality maps for printing or plotting. Click the Open button to
display The Population Growth Rates layout. The Population Growth
Rates layout opens and ArcView's interface changes to display the menus,
buttons, and tools you use for working with layouts. This layout contains the
Population Density view and its symbols, the Countries by Population Density table,
the Birth/Death Rates chart, and additional graphics and text. Use the Zoom In button on the button bar
to look more closely at the layout. |
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From the File menu,
choose Close All. Again from the File menu,
choose Close Project. When you are asked if you want to save changes to the
project, click No. Only the main ArcView
window remains open and active. You've now seen an
ArcView project and some of the documents it can contain (views, tables,
charts, layouts). You've also seen that each document type has its own
interface containing menus, buttons, and tools. In Part B of this lab,
you will perform specific GIS tasks using views and tables in a project. If you want to go on to
Part B of this lab, leave ArcView running. Otherwise, choose Exit from the
File menu to close ArcView. |
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on
the View button bar. You will notice that the button bar now changes to give
you a set of tools that you can use with the attribute table.