IDL Reference Guide: Procedures and Functions

SWAP_ENDIAN

The SWAP_ENDIAN function reverses the byte ordering of arbitrary scalars, arrays or structures. It can make "big endian" number "little endian" and vice-versa.

This routine is written in the IDL language. Its source code can be found in the file swap_endian.pro in the lib subdirectory of the IDL distribution.

Syntax

Result = SWAP_ENDIAN(Variable [, /SWAP_IF_BIG_ENDIAN] [, /SWAP_IF_LITTLE_ENDIAN])

Return Value

SWAP_ENDIAN returns values of the same type and structure as the input value, with the pertinent bytes reversed.

Arguments

Variable

The named variable—scalar, array, or structure—to be swapped.

Keywords

SWAP_IF_BIG_ENDIAN

If this keyword is set, the swap request will only be performed if the platform running IDL uses "big endian" byte ordering. On little endian machines, the SWAP_ENDIAN request quietly returns without doing anything. Note that this keyword does not refer to the byte ordering of the input data, but to the computer hardware.

SWAP_IF_LITTLE_ENDIAN

If this keyword is set, the swap request will only be performed if the platform running IDL uses "little endian" byte ordering. On big endian machines, the SWAP_ENDIAN request quietly returns without doing anything. Note that this keyword does not refer to the byte ordering of the input data, but to the computer hardware.

Examples

; Reverse the byte order of A:  
A = SWAP_ENDIAN(A)