## FLIPUD Reverse the Columns of a Matrix

Section: Array Generation and Manipulations

### USAGE

Reverses the rows of a matrix. The syntax for its use is

       y = flipud(x)

where `x` is matrix. If `x` is an N-dimensional array then the first dimension is reversed.

### Example

The following example shows `flipud` applied to a 2D matrix.

    --> x = int32(rand(4)*10)

    x =

     7 3 1 1
     1 4 4 3
     8 7 8 2
     5 3 1 8

    --> flipud(x)

    ans =

     5 3 1 8
     8 7 8 2
     1 4 4 3
     7 3 1 1

For a 3D array, note how the rows in each slice are flipped.

    --> x = int32(rand(4,4,3)*10)

    x =

    (:,:,1) =

     7 6 0 2
     7 8 6 9
     5 7 0 9
     3 6 9 4

    (:,:,2) =

     8 6 9 5
     9 6 3 3
     3 4 5 4
     7 3 6 9

    (:,:,3) =

     6 4 6 1
     3 6 6 8
     1 5 4 4
     7 9 6 6

    --> flipud(x)

    ans =

    (:,:,1) =

     3 6 9 4
     5 7 0 9
     7 8 6 9
     7 6 0 2

    (:,:,2) =

     7 3 6 9
     3 4 5 4
     9 6 3 3
     8 6 9 5

    (:,:,3) =

     7 9 6 6
     1 5 4 4
     3 6 6 8
     6 4 6 1