GetTheme()

Summary

Gets information about a theme.

 

Changes

Psychological Scaling option added to Version 2019.

 

Syntax

info = GetTheme(string theme_name)

 

Argument	Contents
theme_name	The name of the theme

 

Returns

An array of information as follows:

 

Element	Type	Contents
1	String	The theme type: "Chart", "Class", "Continuous", or "Dot"
2	Array	The theme contents, the structure of which varies by type as indicated below

For Chart Themes

Contents element	Type	Contents
1	String	Chart type: "Bar", "Pie", or "Stack"
2	Array	Field specs (strings) of the fields in the theme
3	Array	Labels (strings) for each field in the theme
4	Array	An array of option-value pairs as described below

 

Option	Type	Contents
Title	String	Title of the theme, as it appears in the legend
Data Source	String	Indicates which data were scanned to determine the minimum and maximum values. If "All" all features are scanned; if "Screen" only features appearing on the screen in the current map are scanned
Minimum Value	Real	Features with values below the mimimum are displayed at minimum size
Maximum Value	Real	Features with values above the maximum are displayed at maximum size
Minimum Size	Real	Minimum pie diameter or total bar length (in points) corresponding to the minimum value (defaults to 0)
Maximum Size	Real	Maximum pie diameter or total bar length (in points) corresponding to the maximum value (defaults to 54)
Psychological Scaling	Boolean	Whether to use perceptual scaling (Flannery method) to compensate for the human tendency to underestimate circle sizes (defaults to "False")
Width	Real	The bar or stack chart width in points (defaults to 14)
3D	Boolean	Whether bar or stack charts are drawn with 3-D effects (defaults to "False")
Direction	String	Whether bar or stack charts are "Vertical" or "Horizontal"

For Classification Themes

Contents element	Type	Contents
1	String	Method: "Categories", "Counts", "Equal Steps", "Equal Weights", "Manual", "Nested Means", "Percents", "Progression", "Standard Deviation", "Quantiles"
2	String	Field spec for the field on which the theme is based
3	Array	Information on the classes in the theme
4	Array	An array of option-value pairs as described below

 

Classes element	Type	Contents
1	Array	An array of class labels (strings), starting with the label for the Other class (if it exists) and followed by the labels for the remaining classes
2	Array	An array of class value definitions; this could be an array of strings; an array of real numbers, or an array of {real low_value, boolean low_inclusive, real hi_value, boolean hi_inclusive}. No definition is provided for the Other class
3	Array	An array of integers indicating the number of features in each class, starting with the count for the Other class (if it exists) and followed by the counts for the remaining classes

 

Option	Type	Contents
Data Source	String	Indicates which data were scanned to determine the minimum and maximum values. If "All" all features were scanned; if "Screen" only features appearing on the screen in the current map were scanned.
Direction	String	Whether the class values in a progression theme are "Decreasing" or "Increasing"
Drop Empty Classes	Boolean	Whether classes containing zero features should be dropped from the theme
Force Value	Real	Forces a break between classes at the specified value (Numeric Categories, Equal Steps, Equal Weight, Quantiles, Standard Deviation)
Include Maximum	Boolean	Whether the maximum value is included or excluded from the range of data
Include Minimum	Boolean	Whether the minimum value is included or excluded from the range of data
Maximum Value	Real	The maximum value to include in a class
Minimum Value	Real	The minimum value to include in a class
Other	Boolean	Whether the Other class was included (for features whose values do not fall into any other class)
Pretty Values	Boolean	Whether the high and low values for each class were rounded to make them more presentable (defaults to "False")
Rate	String	The type of rate to use for a progression theme; one of : Constant, Decreasing, Increasing
Scale	Real	Scaling factor for progression or standard deviation methods
Sort Order	String	If "Descending"classes were created starting with the highest value and working downward; if "Ascending" classes were created starting with the lowest value and working upward (all numeric themes)
Style	Boolean	"True" for a pattern theme; "False" for a color theme
Title	String	Title of the theme, as it appears in the legend
Type	String	The type of progression for a progression theme: "Arithmetic" or "Geometric"
Values	Array	An array containing one element for each class in the theme. The contents of the elements varies by method, as shown in the table below
Weight Field	String	For the equal weight method, the field spec of the numeric field that was used to weight the data values
Zero	Boolean	Whether zero is treated as a missing value (defaults to "False")

 

Method	Contents of the Values Array
Counts	Integers that indicate the number of features in each class
Percents	Real numbers that indicate the percentage of features in each class
Manual (string field)	Strings indicating the value for each class
Manual (numeric field)	One of the following: real numbers indicating the value for each class; or an array of {real low_value, boolean low_inclusive, real hi_value, boolean hi_inclusive} indicating the low and high values for each class

For Continuous Themes

Contents element	Type	Contents
1	String	Field spec for the field on which the theme is based
2	Array	An array of option-value pairs as described below

 

Option	Type	Contents
Title	String	Title of the theme, as it appears in the legend
Data Source	String	Indicates which data were scanned to determine the minimum and maximum values. If "All" all features were scanned; if "Screen" only features appearing on the screen in the current map were scanned
Minimum Value	Real	Features with values below the mimimum are displayed at minimum size
Maximum Value	Real	Features with values above the maximum are displayed at maximum size
Minimum Size	Real	Minimum icon size or line width (in points) corresponding to the minimum value
Maximum Size	Real	Maximum icon size or line width (in points) corresponding to the maximum value

For Dot Themes

Contents element	Type	Contents
1	Array	Field specs (strings) of the fields in the theme
2	Integer	Dot value
3	Array	Labels (strings) for each field in the theme
4	Array	An array of option-value pairs as described below

 

Option	Type	Contents
Title	String	Title of the theme, as it appears in the legend
Data Source	String	Indicates which data were scanned to determine the minimum and maximum values. If "All" all features were scanned; if "Screen" only features appearing on the screen in the current map were scanned

 

Error Codes

Error	Meaning
NotFound	The specified theme does not exist

 

See Also

Function	Summary
GetDisplayedThemes()	Gets a list of themes shown on a layer or selection set
GetThemes()	Gets a list of themes defined on the current layer
GetThemeClasses()	Gets information about the classes of a color or pattern theme
GetThemeOptions()	Gets the options array for a theme
GetThemeStatistics()	Gets statistical information about a class theme
CreateTheme()	Creates a color or pattern theme on the current layer
CreateContinuousTheme()	Creates a continuous (scaled-symbol) theme on the current layer
CreateChartTheme()	Creates a pie or bar chart theme on the current layer
CreateDotTheme()	Creates a dot-density theme on the current layer