The Previous function method sets the previous tile as the current tile and returns the tile data.


See the example for ENVIRasterIterator::GetData.


Result = ENVIRasterIterator.Previous([, ERROR=variable])

Return value

A two-dimensional array containing the tile data.


Keywords are applied only during the initial creation of the object.


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



API Version


See Also

ENVIRasterIterator, ENVIRasterIterator::Next, ENVIRasterIterator::Reset