Previous IDL Reference Guide: Procedures and Functions Next

TRANSPOSE

Syntax | Return Value | Arguments | Keywords | Examples | Version History | See Also

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 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  

IDL prints:

A   INT  = Array[2, 3, 4]  
B   INT  = Array[4, 3, 2]  
C   INT  = Array[3, 4, 2]  

Version History

Original
Introduced

See Also

REFORM, ROT, ROTATE, REVERSE

  IDL Online Help (March 06, 2007)