ENVIDataContainer::HasScalar

Use the HasScalar method to determine if a data container contains a particular data object.

Example

; Start the application

e = ENVI(/HEADLESS)

; Create a data container

container = ENVIDataContainer()

; Open a raster file

File = Filepath('qb_boulder_msi', Root_Dir=e.Root_Dir, $

  Subdir = ['data'])

Raster = e.OpenRaster(File)

; Open a vector file

VectorFile = Filepath('qb_boulder_msi_vectors.shp', $

  Root_Dir=e.Root_Dir, Subdir = ['data'])

Vector = e.OpenVector(VectorFile)

                
; Add the raster and vector to the data container

container.AddScalar, 'raster', Raster

container.AddScalar, 'vector', Vector

; Check if the data container has a named raster object

result = container.HasScalar('raster')

Print, result

Syntax

Result = ENVIDataContainer.HasScalar(Key [, ERROR=value])

Return Value

This routine returns 1 if the data container contains a specified data object. Otherwise, it returns 0.

Arguments

Key

Specify a string identifier with the name of a data object.

Keywords

ERROR

Set this keyword to a named variable that will contain any error message issued during execution of this routine. If no error occurs, the ERROR variable will be set to a null string (''). If an error occurs and the routine is a function, then the function result will be undefined.

When this keyword is not set and an error occurs, ENVI returns to the caller and execution halts. In this case, the error message is contained within !ERROR_STATE and can be caught using IDL's CATCH routine. See IDL Help for more information on !ERROR_STATE and CATCH.

See Manage Errors for more information on error handling in ENVI programming.

Version History

ENVI 5.6

Introduced

API Version

4.2