CreateContinuousTheme()

Creates a continuous (scaled-symbol) theme on the current layer.

theme_name = CreateContinuousTheme(string identifier, array field_specs, array options)

Argument	Contents
identifier	The name you want to use for the theme
field_specs	An array of strings containing the field specs for the fields in the theme

Option	Type	Contents
Title	String	Title of the theme, as it appears in the legend (defaults to theme_name)
Data Source	String	Indicates which data are scanned to determine the minimum and maximum values. If "All" (the default), 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 (defaults to the minimum value found in the data)
Maximum value	Real	Features with values above the maximum are displayed at maximum size (defaults to the maximum value found in the data)
Minimum size	Real	Minimum icon size or line width (in points) corresponding to the minimum value (defaults to 0)
Maximum size	Real	Maximum icon size or line width (in points) corresponding to the maximum value (defaults to 54)

A string indicating the actual name of the theme.

Currently, field_specs must include only a single data field.
For a point layer, a continuous theme is shown by scaling the the size of each point feature.
For a line layer, a continuous theme is shown by scaling the the width of each line feature.
For an area layer, a continuous theme is shown by scaling the size of an icon displayed at the centroid of each area feature. The icon settings are controlled using SetIcon(); for more information, see Theme Styles.
To display the theme, call ShowTheme(); for more information, see Themes.
All fields in field_specs must be mappable to the current layer.
CreateContinuousTheme() scans the data for the layer to find an appropriate minimum and maximum value.
If both the minimum and maximum value options are used, no scan is performed.

// Scale cities in size based on population

thm = CreateContinuousTheme("City Population", {"City.Population"},)

ShowTheme( , thm)

Error	Meaning
Escape	The user interrupted scanning of the data
Error	An argument or option has the wrong type or the wrong number of values; or an error occurred while scanning the data
NotFound	There is no current layer, or the specified field(s) do not exist on the current layer

Function	Summary
CreateTheme()	Creates a color or pattern theme on the current layer
CreateChartTheme()	Creates a pie or bar chart theme on the current layer
CreateContinuousTheme()	Creates a continuous (scaled-symbol) theme on the current layer
DestroyTheme()	Removes the definition of a theme from the current layer
GetTheme()	Gets information about a theme
GetThemes()	Gets a list of themes defined on the current layer
ShowTheme()	Displays a theme on the current layer