# Microsoft PowerPoint - Introduction to ArcGIS 1

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```					Introduction to ArcGIS

Prepared by:
Florida International University Libraries
Maps & Imagery User Services
February 2008
http://mius.fiu.edu

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1.1 What is GIS…...............................................................pg.3
1.2 Properties of Geographic Data…........................................pg.4
1.3 Representation of Geographic Data…………………………pg.5
1.3.1 Vector Data Formats…………………………....pg.8
1.3.2 Raster Data Formats…………………….……...pg.9
1.4 GIS Data Layers…………………………………….......pg.10
1.5 Layers, Features and Tables…………………………...pg.11
2. Introduction to ArcCatalog
2.1 Accessing ArcCatalog……………………………..........pg.13
2.2 Geodatabases…………..……………………………….pg.14
2.3 Shapefiles..……………………………………………….pg.15
2.4 Previewing Shapefiles…………………………………..pg.16
2.6 Image Files……………………………………………….pg.18
2.7 Image File Types………………………………………...pg.19
3. Introduction to ArcMap
3.1 Adding Data to a Map………………………...…………pg.22
3.2 Editing a Map in ArcMap...………………………..........pg.23
4.1 Data Sources…………………………………………….pg 25

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1.1 What is GIS?

GIS - Geographic Information Systems/Science

A method of organizing, distributing, analyzing, and
visualizing geographic data

•Data Extension of Database Management Systems
(DBMS)

•Graphic interface for data retrieval and distribution

•Data visualization

•Spatial analysis

•Modeling and decision-making

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1.2 Properties of Geographic Data

Geographic data links place, time, and attributes

1.   Place (Spatial): location that can be registered
and illustrated based upon a geographic
reference. (Where?)
2.   Time (Temporal): information about how a
parameter changes over time. (When?)
3.   Attributes (Tabular): descriptive data about the
characteristics of the spatial or temporal
elements. (What?)

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1.3 Representation of Geographic Data

Raster and Vector are two methods of
representing geographic data in digital format
(Longley, P. et al)

Vector:
• point : to record the location of objects in a 2-
dimensional space
• lines: between two points (directions and length)
• polygons: closed vectors (area, centroids, and
perimeter)
Raster: (re-visiting)
• use a fixed grid and record information about
each element on the grid. (Satellite images, aerial
photos, etc.)

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Vector
A river
(Line)

A house
(Polygon)

A tree
(Point)

Raster
House

Tree

River

(Cells, Pixels)

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Moving from reality to GIS Representation

Reality         a river, house, tree
Conceptualization         entity attributes,
relationship

Data Model         Vector, Raster
Data structure        geodatabases, coverage,
shapefiles, TIGER, GRID, TIN, DEM, Image etc

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1.3.1 Vector Data Formats

ESRI vector formats:

Shapefiles -- .shx, .shp .dbf

ArcInfo Coverage -- store all attribute in an “info”
folder, and all spatial features, e.g. points, arc,
labelpoints, polygons, routes, regions, and
annotation in the space called coverage.

Geodatabase – contains features class, feature
datasets, tables, annotation, relationships.

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1.3.2 Raster Data Formats

ESRI Raster formats:

• ArcInfo Grid
• ERDAS Imagine -- .img files
• .jpeg, .tiff
• MrSid -- .sid
• TIN (3D data model)
•Import files – USGS’s DRG, DOQ, DEM
•remotely sensed images (LandSAT) , aerial
photographs

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1.4 GIS Data Layers

•A GIS map contains layers
•Layers contains spatial features or
surfaces

Features -- point, line, polygon

Surface - a raster or matrix of pixels with
numeric values can represent a surface

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1.5 Layers, Features and Tables

•   Each map feature represents a geographic
object
•   Each theme of map features can contain
descriptive data (attribute data)

Features have spatial relationships

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2. Introduction to ArcCatalog

ArcCatalog is part of a GIS software package
manufactured by ESRI. ArcCatalog allows you
to examine and organize different types of
geographic data. Using ArcMap you can
map. In this exercise you will be introduced to
some of the features of ArcCatalog.

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2.1 Accessing ArcCatalog

Follow the steps below to access ArcCatalog
and the geodatabase you will work with for this
lesson.

2. Select All Programs >> ArcGIS >> ArcCatalog
3. In the Location panel, type “P:\MIUS
Workshops\Intro_To_ArcGIS_Data” and press Enter.

Tools

Your current view may not look exactly the same as below.
In the view below, the geodatabase dade, located in the
Intro To ArcGIS Data folder, has been opened, and the
shapefile landuse has been selected. This file contains
polygons, which show land use in Miami Dade County.

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2.2 Geodatabases

Geodatabases are relational databases
that contain geographic information in the
form of feature classes and tables.
the + sign, to the left of the
Data folder.
2. Read the names of the feature class
and table files listed under
3. Click on the + sign to the left of
list.
4. From the file names, what
information do you think this
County? ________________
_____________________________

These files are examples of vector data.

Vector Data are geographic information
represented by points, lines and polygons.

In ArcCatalog feature classes store vector data,
with annotation and dimensions.

Tables may contain additional attributes for a
feature class or geographic coordinates. 14
2.3 Shapefiles

These files are shapefiles.
Shapefiles contain a single feature class; whereas a
geodatabase contains several feature classes where
relationships between the feature classes can be
defined.

Shapefile Symbology

Point            Line          Polygon
1. Click once on
the shapefile
landuse.
2. Examine the
information
associated with each
tab.

The first tab is the
Contents tab. It shows
the name and type of file.
This file is a shapefile.
The symbol for a
shapefile is shown at left.
may display a thumbnail
image of the contents
that has been created as
an alternative.
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2.4 Previewing Shapefiles
The second tab, Preview, shows a representation of the information in
the selected shapefile. The data can be previewed as the
geographical representation (points, lines, or polygons) or as the
attribute table containing the actual data used to place the points,
lines or polygons on a map.

1. With landuse.shp open. Select
the Preview tab.
2. At the bottom of the Preview
window, click the dropdown arrow
and select Geography.
3. What do the polygons in the
preview represent?__________
____________________________

4. Next, click the dropdown arrow and select Table.
5. What kind of information is shown now?
_____________________________________________

In the Preview window you can also create a thumbnail image for the

6. Select Geography view in the
Preview window.
7. Click the Zoom In tool on the
toolbar.
8. With draw a box around an area
of the preview that best
represents the contents.
9. Click Create Thumbnail .

10. Select the Contents tab, and view the new        16
thumbnail image you have created!

which is the third tab.

tabs.

provides keywords, an abstract of the data and the purpose
of the data.
describes the map projection.      A map projection is a
mathematical representation of the curved surface of the
earth in a two-dimensional flat map.
provides information about the content of the attribute table.
An example of spatial metadata is shown below.

2.According to the
purpose of the
data?______________________
___________________________
3.How many records are
shapefile?________________

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2.6 Image Files

Image files      are another file type that can be viewed in
ArcCatalog.

Images and grids are rasters data that represent
geographic features by dividing the feature into discrete
squares called cells or pixels.

Cells are laid out in a grid. Each cell is given a location in relation to
a reference point. The value of the cell describes the feature being
observed. In an aerial photograph, the cell values represent the
amount of light reflecting off the earth's surface.

1.   In ArcCatalog, select the image file
africa_150m_earthsat.jp2.
2.   Select the Preview tab.
3.   Select the zoom in tool.
4.   Draw a small box in the center of the image.
Repeat this step until you can see the
individual cells like the diagram below.

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2.7 Image File Types

Aerial Photos
Image File Types
Digital Elevation Models (DEM)

LIDAR (Light Detection and Ranging) is a form of
remote sensing where lasers, mounted in
airplanes, send pulses of light to the ground and
airplane. Locations are precisely determined using
geographical positioning systems (GPS). Using
mathematical interpolation programs, values for
the elevation are placed in cells of a grid to
produce a digital elevation model (DEM).

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3. Introduction to ArcMap

ArcMap is part of a GIS software package
manufactured by ESRI. It allows you to load and
display different types of geographic data. Using
ArcMap you can incorporate information directly
by ArcMap can be published for use or placed on
the Internet. In this exercise you will be introduced
to some of the features of ArcMap.

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3.1 Adding Data to a Map

Now that we have examined different formats of geospatial data
using ArcCatalog, we will use some of that data to make a map.

1. Open ArcMap by clicking once on
the globe in the ArcCatalog toolbar.

2. When ArcMap opens, select the
option A new empty map.
3. Click OK.

We can add data to ArcMap by dragging the file from the Table

hold the left mouse
button, and drag the
file to ArcMap as
shown.

the file
ArcMap.

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3.2 Editing a Map in ArcMap

In this Part, we will zoom into a portion of the map containing a fire
station, change the symbol for fire stations and add labels to the roads.

1. Select the Zoom tool.
2. Hold down the left mouse button and draw a box
around one of the fire stations.
3. Release the mouse to get a closeup view.

Changing Symbols

click the diamond symbol.
5. In the Symbol Selector
dialog box, choose a symbol
shape, color and size.
6. Click OK.

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7. Right click on the layer major_roads_zip.
8. Select Label Features.
9. What road is the fire station, in view on your map,
located on? ________________________________
10. Add labels to the fire station.
11. Change the color of the streets to red.

In this exercise you have learned about some different
formats for geospatial data in ArcCatalog. Then you
learned how to add data to ArcMap, change map symbols
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