How can I flip a row vector without using flip(lr) function?

I want to write a function that it can flip a row vector without flip(lr) function.

if true
  % A=[1 2 -3 4]
    And output must be:
    B=[4 -3 2 1]
end

Answer 1

[Star Strider]

Reverse the indices:

A = [1 2 -3 4];
B = A(numel(A):-1:1)

B =
     4    -3     2     1

[denizakyol]

Thank you.

[Star Strider]

As always, my pleasure.

[Image Analyst]

You can simply use "end" - you don't need to call the numel() function:

B = A(end:-1:1)

end still works inside the parentheses even though it's the first thing in there instead of the last.

[Star Strider]

@Image Analyst — Good point. Thank you.

I wanted to make my code straightforward, the reason I wrote it as I did. I was not certain if using end would do that.

[denizakyol]

@Image Analyst Thank you so much. The end function is so helpful at all matrix operations. I would not forget anymore.

Answer 2

[Walter Roberson]

B = flipud(A.').';

Answer 3

[madhan ravi]

A=[1 2 -3 4]

B=wrev(A)

[denizakyol]

Thank you but I don't have Wavelet Toolbox. I want to write this function with matrix operations.

Answer 4

[Saad]

how to conver a matrix without using (flip function's)?for example

a= 1 2 3 4 b=4 3 2 1

5 6 7 8 8 7 6 5

9 10 11 12 12 11 10 9

13 14 15 16 16 15 14 13

[Star Strider]

@Saad —

The same as I originally posted, with an additional row dimension —

a = [1:4; 5:8; 9:12; 13:16]

a = 4×4

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

b = a(:,size(a,2):-1:1)

b = 4×4

4 3 2 1 8 7 6 5 12 11 10 9 16 15 14 13

.

[Stephen23]

b = a(:,end:-1:1)