Maptitude GISDK Help

CreateExpression()

Summary

Creates an expression field on a view.

 

Syntax

expr = CreateExpression(string view_name, string expr_name, string expression, array options)

 

Argument Contents
view_name The view on which to create the expression field
expr_name The name you want to use for the expression field
expression An expression

 

Option Type Contents
Type String The data type of the expression field; supported types are "Integer", "Real" or "String"
Width Integer The display width
Decimals Integer The number of displayed decimals

 

Returns

A string that contains the actual name of the expression field.

 

Notes

Example

pd_field_name = CreateExpression("U.S. States", "Pop Density", "Population/Area", )

 

Error Codes

Error Type Meaning
Error The expression is null or invalid; expr_name is null or invalid; or the expression field type is not specified and cannot be determined
NotFound The specified view does not exist, or the input view_name is null and there is no current view

 

See Also

Function Summary
VerifyExpression() Verifies the validity of an expression
DestroyExpression() Destroys an expression field
GetExpressions() Returns an array of all expression fields defined in a view
GetExpressionInfo() Returns information about an expression (formula) field
SetColumnArray() Sets the columns displayed in an editor

 

 

©2025 Caliper Corporation www.caliper.com