MATLAB^®

swapbytes - Swap byte ordering

Syntax

Y = swapbytes(X)

Description

Y = swapbytes(X) reverses the byte ordering of each element in array X, converting little-endian values to big-endian (and vice versa). The input array must contain all full, noncomplex, numeric elements.

Examples

Example 1

Reverse the byte order for a scalar 32-bit value, changing hexadecimal 12345678 to 78563412:

A = uint32(hex2dec('12345678'));

B = dec2hex(swapbytes(A))
B =
    78563412

Example 2

Reverse the byte order for each element of a 1-by-4 matrix:

X = uint16([0 1 128 65535])
X =
      0      1    128  65535

Y = swapbytes(X);
Y =
      0    256  32768  65535

Examining the output in hexadecimal notation shows the byte swapping:

format hex

X, Y
X =
   0000   0001   0080   ffff
Y =
   0000   0100   8000   ffff

Example 3

Create a three-dimensional array A of 16-bit integers and then swap the bytes of each element:

format hex

A = uint16(magic(3) * 150);
A(:,:,2) = A * 40;

A
A(:,:,1) =
   04b0   0096   0384
   01c2   02ee   041a
   0258   0546   012c
A(:,:,2) =
   bb80   1770   8ca0
   4650   7530   a410
   5dc0   d2f0   2ee0

swapbytes(A)
ans(:,:,1) =
   b004   9600   8403
   c201   ee02   1a04
   5802   4605   2c01
ans(:,:,2) =
   80bb   7017   a08c
   5046   3075   10a4
   c05d   f0d2   e02e