TRANSPOSE

The TRANSPOSE function returns the transpose of Array. If an optional permutation vector is provided, the dimensions of Array are rearranged as well.

Syntax

Result = TRANSPOSE( Array [, P] )

Return Value

Returns the reflection of the array along a diagonal.

Arguments

Array

The array to be transposed.

P

A vector specifying how the dimensions of Array will be permuted. The elements of P correspond to the dimensions of Array; the ith dimension of the output array is dimension P[i] of the input array. Each element of the vector P must be unique. Dimensions start at zero and can not be repeated.

If P is not present, the order of the dimensions of Array is reversed.

Keywords

None.

Examples

Note
Also see Transposing Images (Image Processing in IDL) for a more extensive example.

Example 1

Print a simple array and its transpose by entering:

; Create an array:
A = INDGEN(3,3)
TRANSA = TRANSPOSE(A)

; Print the array and its transpose:
PRINT, 'A:'
PRINT, A
PRINT, 'Transpose of A:'
PRINT, TRANSA

IDL prints:

A: 
   0  1  2 
   3  4  5 
   6  7  8 
 
Transpose of A: 
   0  3  6 
   1  4  7 
   2  5  8

Example 2

This example demonstrates multi-dimensional transposition:

; Create the array:
A = INDGEN(2, 3, 4)

; Take the transpose, reversing the order of the indices:
B = TRANSPOSE(A)

; Re-order the dimensions of A, so that the second dimension
; becomes the first, the third becomes the second, and the first
; becomes the third:
C = TRANSPOSE(A, [1, 2, 0])

; View the sizes of the three arrays:
HELP, A, B, C