GIS Fundamentals: Supplementary Lessons with ArcGIS
Introduction to ArcGIS
Lesson 1: Introduction to ArcGIS
What You’ll Learn:
-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
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.
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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 then elect 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.
Table of
Contents
window
pane
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.
2
Data View
pane
pawindow
pane
GIS Fundamentals: Supplementary Lessons with ArcGIS
Introduction to ArcGIS
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.
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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: Intro Symbology 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.
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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.
Select Insert 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.
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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.
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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 File Export
Map (see figure left below).
The steps below are shown in the
video: Export Print
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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 Relative Paths.
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
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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.
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There is a fix, by specifying relative path
names. To do this, left click on FileMap
Document Properties (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
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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.
After adding the data, left click on the name of the layer (wet_lands.shp) and right
click to select Properties.
This opens a Layer Properties window, with several actions you can begin by
activating tabs along the top of the
window (see the graphic a few
pages above).
Video: More Symbols
Use the General tab (furthest to
the left) to change the Name of the
layer to Hugo Wetlands.
Left click on the Symbology tab
(located near the top center of the
tabs). This will open a window, a
bit simpler to that shown at right.
1) In the upper left select
Categories, then Unique
Values.
2) Select Wetland_ty using the down arrow next to the Value Field.
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3) Click on the Add All Values. All the wetland types will now be shown.
Uncheck the box to the left of the “all other values”.
4) Change the color scheme for the map to colors you prefer.
Since the U value (which means Uplands) is such a large part of the map let’s
make it blank to make the map more readable.
Left click twice quickly on the colored box to the left of the U value.
Left-click Hollow from the symbol selector window and then OK.
Select Apply and then OK.
As before, switch to the Print Layout View and add a Title, Legend, Scale Bar,
North Arrow and your name/date. Practice selecting the map, title, legend and
resizing each item. Move these
objects around into a pleasing
arrangement. Your map should look
similar to the image at the right/below.
Export this map to a PDF.
Finally, save this map as a map project
file; File  Save As. (Video: Saving
Project). Note that as noted above,
with simple projects it is usually a good
idea to save the project in the same
directory as the data, and set the path
names relative.
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Data Frames
When you first started ArcGIS, it automatically created a working area, called a
“Data Frame.” It named this first working area “Layers,” as
shown by the yellow stack in the table of contents. It is perhaps
easiest to think of this data frame as analogous to a desktop,
onto which you place data layers. Just as you may have several desks in a room,
you may have several data frames in an ArcMap project.
To carry this analogy further, you may place different data on each “desktop”
represented by each data frame. You may also display a different area, use
different symbology, and different coordinate systems for each “desktop”, or data
frame.
A map may have several DATA FRAMES. When you add data layers to a map
the data will be placed in the “active” frame; by default this is active frame is
called “Layers”. This exercise will only use the default DATA FRAME called
“Layers”.
Setting Data Frame Properties
To control DATA FRAME options, use the table of contents pane (remember, the
narrow, vertical sub window on the left side of the main ArcMap window):
Left click twice on “Layers” with the yellow stack icon near the top of the table of
contents display:
This will display a Data
Frame Properties window
(see at right). Various tabs
control various properties for
a data frame, such as the
name (with the General tab),
the size of the frame (Size
and Position), plotting grids
(Grids tab), the coordinate
system (discussed next
week), or whether to draw a
bounding frame (Frame tab).
Before leaving the data frame
properties screen, select
some of the other tabs (see
what operations they control).
To leave the data frame
properties window, left click
on the OK.
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Practice and More Tools
Create a new project (a “Blank Map”) and add
the following layers to your map:
40_corners,
Cl_roads (NOTE: “CL_ROADS” NOT “ROADS”)
Streams
Iverson_drg
Setting the Layer Order
Notice that the table of contents lists the point data layer on the top, then the two
line data layers (roads and streams), then the raster data layer (Iverson_drg).
We can manually shift data set order in the layer stack.
Left click on the Iverson_drg layer and hold the mouse button down.
While holding down the mouse button, drag the layer toward the top of the stack.
As you do a black line will show the new position in the layer stack. Move this
layer to the top of the stack and release the button, dropping the layer.
The rearranged layers now look different because the Iverson_drg covers up the
other three layers.
Move the Iverson_drg layer back to the bottom of the stack.
To widen the table of contents (TOC) pane,
left click and hold on the vertical line
between the TOC and the data view, and a
two-arrowed line will appear (see figure at
left). Stretch the line to the right, widening
the TOC to see all of the layer title
information.
Change the names of the data sets
displayed in the table of contents through
Drag it this
way
-selecting the layer by right clicking on the
name, then
-selecting Properties General tab
-entering text in the Layer Name textbox
-left clicking OK
Pan, zoom, re-arrange layers, and apply symbology until your map appears
similar to the image on below.
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Measuring Distances and Areas
Find the gravel pit and
lookout tower features by
panning/zooming about
the map, then pan/zoom
so that both just fit in the
window (see figure at
right).
These are in sections 29
and 32, south of the
points in the 40_corners
data set, and southwest
of the Cloquet airport.
Find the Measure
Distance icon, and left
click on it to activate the
measure tool (it is
usually with the
pan/zoom tools).
Measure
the
Distance
between
the
Lookout
Tower and
the Gravel
Pit
Video: Measure Tool
Use the measure tool to estimate the distance between the gravel pit and the
lookout tower (left click, hold, drag, and release).
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You can change the measurement units displayed by:
-left clicking on the triangle near the upper middle of the Measure window
-left clicking on Distance
-selecting the desired units
Now measure some other distances.
Pressing Escape (ESC) clears & starts
a new measuring operation.
Measure the area of one of the
sections, the numbered red “squares”.
How many square miles is a section?
Quit the measure tool (remember, left
click on the black arrow that is part of
the pan/zoom group).
Use the Zoom and Pan
Icons to make your map
cover an area similar to
the figure shown to the
right.
Now compose and print
or export another map.
Switch to the Layout
View as described
earlier, and use the
Insert menu to add a
title, North arrow and
scale bar.
You may use these
layout zoom tools if you
want to inspect map elements before outputting a layout, for example, to better
place, size, or align the legend, North arrow, or other
map features, or to resize maps.
If you click on the map, you will see “blue handles”
appear at the corners (shown at right). These are
your change points. You can click and drag these to
resize the display area, for example, to make space
for a legend, title, north arrow, or other elements you
don’t want to place over the spatial data.
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Create your map similar to the figure below, with a title, name, legend, north
arrow, and scale.
NOTE: Do not include the Iverson_drg in your legend.
(Use the < to move the iversong.drg back from “legend items” to “map items” in the Legend
Wizard)
Export this map as a pdf.
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Multiple Data Frames in One Document
Use File New, select Blank Map.
In the new Map document, Use Insert Data
Frame.
Video: Data Frames
You should now see two icons that are
yellow “layer stacks,” one named “Layers”,
and a second named “New Data Frame” in the table of contents (TOC).
Right click on the “New Data Frame”,
click on Activate in the dropdown menu.
Notice that the New Data Frame now
appears in bold in the TOC. Right click on
data frame icon, and activate it. You may
data frames in a map project. The
currently active data frame will appear in
bold letters in the TOC.
the “Layers”
have several
Each data frame specifies a different map, with its own data layers, coverage,
and coordinate system, and other map properties
Activate the data frame called “Layers”
and use the Add Data to add the vegetation.shp and the iverson_drg.img data
layers found in the \L1 directory
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Right click over the data frame named “Layers” in the table of contents
From the drop-down menu, select Properties (at the very bottom, just below
Activate)
This should display a Data Frame Properties menu.
Select the General tab. Specify a Name of “Inset”. Then
left click on Apply and OK
Your data view and table of contents should be similar
to the figure at right. Note that you have changed the
names for your data views in your table of contents
window.
Select the New Data Frame then right click and Activate this data frame.
Load the vegetation, cl_roads, and streams data layers in this new data frame,
and rename the frame as “Main Panel.”
Activate the layout view, set the page to landscape (File -> Page and Print
Setup…), and left click on one of the data frame panes to activate it. Use the
blue edge “handles” to resize it so you have an inset and main panel to create an
inset map, similar to that shown below.
Note that you don’t need to print this map, but you should understand the
process, as
next week and
in future labs
you’ll have to
produce multipanel map.
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Part 2: GeoDatabases
You may wonder about the data layers you have just used for your two maps,
Lakes, Roads, and wet_land. These layers are shapefiles, a special file type
defined by ESRI for storing spatial data. Shapefiles are a group of files that
share a file name but have different extensions, such as .shp or .dbf or .prj.
ESRI subsequently created a more complex data structure, called a
GeoDatabase.
You typically create the GeoDatabases (or the simpler/older shapefiles) by leftclicking on the catalog tool:
You may right-click on a folder in the directory tree, then scroll down to New,
Personal GeoDatabase (see
figure) to create a new
geodatabase.
Our lab exercises will
primarily use shapefiles
because they are adequate
for demonstrating most basic
concepts. However, we’ll at
least introduce how to create
a GeoDatabase, and
describe some of the things
you may do with them.
If your USB drive does not
show up, left click on the
connect to folder option in the Catalog (see right arrow in the figure, above), and
navigate through the menu tree to your drive.
Create a new personal GeoDatabase
You will now create files to hold data layers, data tables, or other information.
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Right click on the GeoDatabase
you just created, the scroll down
to New, then Feature Dataset in
the set dropdown menus
In ESRI’s parlance, a Feature
Dataset is a collection of related
spatial data, usually data layers
and other geometric constructs.
You may want to hold clusters of
data together, for example, data
layers on river locations, lakes
along those rivers, and dams
associated with each lake. The
river, lake, and dam data are
Feature Classes, and additional
tables and network connections
may also be stored in the feature
dataset.
You may create a new feature dataset, feature class, or table by selecting File >
New, then the GeoDatabase item you’d like to create. You’ll be prompted by a
series of menus asking you to specify the characteristics of the item.
In this example, name it something like MyData
Enter a name, and click Next.
Specify a coordinate system
(here Projected-CountyMinnesota-Anoka Feet), then
Next
Leave the Vertical at the default
<None>, and left click on Next
Accept the defaults for the
Tolerances on the next window,
and left click on Finish.
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You’ve just created an empty feature dataset. I find the description confusing,
because it doesn’t contain any data yet. You have to put what ESRI has called
feature classes (which will contain data) within this feature dataset.
You do this by right
clicking on the
“mydata” feature
dataset you just
created, and scrolling
to New, Feature Class
on the dropdown
menus that appear:
Name the feature
class, don’t bother with
an alias, and select the
type – typically point,
line, or polygon for
vector, although more
complex options,
which we won’t
describe, are also
available. Create a polygon feature class, then left click on Next.
Specify the data fields for the
feature class. ObjectID and
SHAPE are typically defined
by default for basic feature
classes. You may add new
fields (variables) that hold
information about each
feature. For example, for a
stream feature class, I could
define the stream_size,
order, type, name, etc. I
would specify an appropriate
data type for each, e.g.,
stream_size as a long
integer, order as a short
integer, type and name as
text, etc.
Click Finished.
22
GIS Fundamentals: Supplementary Lessons with ArcGIS
Introduction to ArcGIS
When you click finished, you should now get a
view that shows your new feature database,
and a nested feature class in a GeoDatabase,
as on the right. The feature class doesn’t have
anything in it (we will cover data entry in
another lesson), but these are the creation steps. The shapefiles we will use are
adequate for the simplest of datasets and operations, and are most appropriate
for this introductory class. Most of the operations we introduce in this class can
be well-supported with the simpler shapefiles. However, there are advantages for
the more complex GeoDatabases for larger, more complex, longer-lived data.
Topologies in GeoDatabases
Open a new project (Blank Map), and display the following layers found in the
L1\Example_topology GeoDatabase, in the testdata feature dataset:
-point_layerX
-line_layerC
-line_layerD
-layerA
-layerB
These are very simple data layers that we’ll use to introduce vector topology.
Now, we want you to look at the video topology.
In particular, we want you to:
1) examine the data layers, using the selection tool , and
specifically note:
-the polygon overlap in layer A,
-the lack of containment of all polygons of layers A by layer B
-the adjacency of line_layerC and line_layerD to the polygon layers,
-the partial containment (coverage of) the point_layerX by layerA
Clicking on objects with the selection tool will show a cyan outline of the
features. Note that as you alternately click on polygons, you can see how
features overlap.
2) Now use the Add Data button, add the Example Topology Database, testdata,
testdata_topology. Answer no to the question about adding the participating
data sets, you’ve already added them.
23
GIS Fundamentals: Supplementary Lessons with ArcGIS
Introduction to ArcGIS
3) Note how the rules
are applied to the
other data layers.
Note that the errors
and highlighted in
RED.
You can look at the
topological rules by
right-clicking on the
topology in the table
of contents, then
selecting
Properties, at the
bottom of the dropdown menu, and the
Selection tab (see
right). This lists the
rules, and the data pane shows where the rules are broken in red.
4) Create a layout of
the data and
topological errors,
with an appropriate
legend and name,
scale bar, north
arrow, export this to
a pdf, and turn it in.
The data view will
look something like
the figure right:
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