# flipud

Flip array up to down

## Description

example

B = flipud(A) returns A with its rows flipped in the up-down direction (that is, about a horizontal axis).

If A is a column vector, then flipud(A) returns a vector of the same length with the order of its elements reversed. If A is a row vector, then flipud(A) simply returns A. For multidimensional arrays, flipud operates on the planes formed by the first and second dimensions.

## Examples

collapse all

Create a column vector.

A=(1:10)'
A = 10×1

1
2
3
4
5
6
7
8
9
10

Use flipud to flip the elements of A in the vertical direction.

B = flipud(A)
B = 10×1

10
9
8
7
6
5
4
3
2
1

The order of the elements in B is reversed compared to A.

Create a 3-by-3 cell array of characters.

A = {'a' 'b' 'c'; 'd' 'e' 'f'; 'g' 'h' 'i'}
A = 3x3 cell
{'a'}    {'b'}    {'c'}
{'d'}    {'e'}    {'f'}
{'g'}    {'h'}    {'i'}

Change the order of the rows in the vertical direction by using flipud.

B = flipud(A)
B = 3x3 cell
{'g'}    {'h'}    {'i'}
{'d'}    {'e'}    {'f'}
{'a'}    {'b'}    {'c'}

The order of the first and third rows of A is switched in B, while the second row remains unchanged.

Create a multidimensional array.

A = cat(3, [1 2; 3 4], [5 6; 7 8])
A =
A(:,:,1) =

1     2
3     4

A(:,:,2) =

5     6
7     8

A is an array of size 2-by-2-by-2.

Flip the elements on each page of A in the vertical direction.

B = flipud(A)
B =
B(:,:,1) =

3     4
1     2

B(:,:,2) =

7     8
5     6

The result, B, is the same size as A, but the vertical order of the elements is flipped. The operation flips the elements on each page independently.

## Input Arguments

collapse all

Input array, specified as a vector, matrix, multidimensional array, table, or timetable.

Data Types: double | single | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | logical | char | string | struct | cell | table | timetable | categorical | datetime | duration | calendarDuration

Complex Number Support: Yes

## Tips

• flipud(A) is equivalent to flip(A,1).

• Use the fliplr function to flip arrays in the horizontal direction (that is, about a vertical axis).

• The flip function can flip arrays in any direction.

## Version History

Introduced before R2006a