Thematic Mapping

ArcView_module_3May 12, 1:30 PM

Outline Getting a data into ArcView

Choosing a Legend

Choosing a Symbol

ArcView Shapefiles

File extension

Functions

.shp the feature geometry

.shx an index to the feature geometry

.dbf the associated dBASE file of attribute information

Shapefiles come in the following three files

Getting a data into ArcView

How to add a Theme Click the Add Theme button

Feature data will be displayed by default

Getting a data into ArcView

The Table of Contents

Getting a data into ArcView

The Table of Contents shows…

Getting a data into ArcView

The name of each theme in the view The feature type of each theme The legend for each theme Whether a theme is on or off The order the themes are drawn in Which themes are active Which theme is editable

Steps for making thematic map

1. Choose a theme

2. Choose a Legend

3. Choose a Symbol

How to open Legend Editor

Choosing a Legend

Double-click a theme in the Table of Contents to open the Legend Editor

Legend Types

Single Symbol displayed with the same colors and

symbols. useful when you only need to show

where a theme’s features are located.

Choosing a Legend – legend type

Graduated Color displayed with the same symbol type,

but different colors shade (e.g., dark blue to light blue) or

tone (e.g., warm tone, cold tone) represents the progression of values for a data attribute

Choosing a Legend – legend type

Graduated Symbol symbolize data that expresses size or magnit

ude. only available for point and line data.

Choosing a Legend – legend type

Unique Value each unique value in a theme is

represented with a unique symbol effective for displaying categorical

data.

Choosing a Legend – legend type

Dot Density displayed with a number of dots

corresponding to a value only available for polygon data

Choosing a Legend – legend type

Chart displayed with a chart the components of the chart

correspond to data attributes you specify

the size of each part in a chart is determined by the value of each data attribute

good for displaying the values of many attributes

Choosing a Legend – legend type

Choosing an Appropriate Legend

depends on characteristics of the attributes of interest

(e.g. categorical vs numeric)(e.g. normalized or not)

feature type of the theme (e.g. point, line, polygon)

Choosing a Legend

Choosing an Appropriate Legend

Is your data categorical, like names of places or types of roads? Use Unique Value

Is your data ranked, like best sales territory to worst sales territory? Use Graduated Symbol for point/line feature Use Graduated Color for polygon feature

Choosing a Legend

Choosing an Appropriate Legend Is your data raw count, like population or barr

els of crude oil? Use Dot Density for polygon feature Use Graduated Symbols for point/line feature

Is your data normalized, like percentage data or population per unit of area? Use Graduated Color for polygon feature Use Graduated Symbol for point/line feature Use Chart for several normalized attributes

Choosing a Legend

Steps for making thematic map

1. Choose a theme

2. Choose a Legend

3. Choose a Symbol

Choosing a Symbol

How to open Symbol Window

Choosing a Symbol

Double-click here to open the Symbol Window

Color Palette: choose a color for all feature types and text

Palette Manager: customize palettes

Symbol Symbol PalettesPalettes

Symbol Palettes Fill Palette: choose how to fill the

polygon (e.g., color-filled, empty, pattern-filled).

Pen Palette: choose the pattern for the line (e.g., solid, dashed, double).

Marker Palette: choose the marker suitable for the point theme (e.g., basic shapes

Font Palette: select a font to draw the label

Choosing a Symbol

Color Palette Unlike the Symbol Palette, the

Color Palette applies to all feature types and text.

Choosing a Symbol

Point, Line

Polygon

Text

Auto-labeling

1. choose a text symbol/color from font palette/color palette

2. choose a theme3. choose the Auto-label… from the

Theme menu4. choose a field to be used for

labeling5. choose a labeling option

Choosing a Symbol

Auto-labeling

Choosing a Symbol

Unchecked not to display overlapping labels

Checked to make labels dependent on a map scale

Checked not to display duplicate labels

Map Tips use color/shape to represent qualitative attri

butes (i.e. type) [unique value]

use shade/size to represent quantitative attributes (i.e. magnitude) [graduated color/graduated symbol]

normalize attributes for choropleth map due to the effect of variant area size [graduated color map with normalization]

Choosing a Symbol

How to load additional markers

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Population in Census Tract5.444 - 2186.1662186.166 - 5024.7355024.735 - 8294.1188294.118 - 12623.76212623.762 - 18251.656

Major Road

Õ Hospital

Hospitals in the City of Buffalo

2 0 2 4 Miles

N

select ESRI font (e.g., ESRI cartography) from the font palette, and then click “Create Marker” button at the bottom.

Choosing a Symbol

How to make a transparent polygon symbol set Background to nothing while

Foreground is set to pattern-filled.

Choosing a Symbol