# creating a function to output the invert the numbers in an array

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Alexandra on 28 Oct 2012
A = [ 1 2 3 4 5 6]
A = 6 5 4 3 2 1
when an array is entered, the function will display all elements on a row and all rows in inverted order.
I am having trouble creating a function to do the above for both vectors and matrices. I am to do this without using flip functions.
any help is appreciated ~
Alexandra
Walter Roberson on 29 Oct 2012

Image Analyst on 28 Oct 2012
This sounds like a homework problem ( http://www.mathworks.com/matlabcentral/answers/8626-how-do-i-get-help-on-homework-questions-on-matlab-answers). Hint: use a for loop with an increment of -1 to go backwards:
for row = lastRow: -1 : 1
same for the columns. To determine the last row, use the size() function. Use fprintf() or disp() to display. Also, type
doc colon
on the command line to learn how the colon operator works. Post back here with your attempt if you're still having trouble.

Chris A on 28 Oct 2012
A = [ 1 2 3 4 5 6]';
b=reshape(sortrows(horzcat(A, ((numel(A):-1:1)')), ),[],1);
b(1:6),

Andrei Bobrov on 29 Oct 2012
Edited: Andrei Bobrov on 29 Oct 2012
ii = numel(A):-1:1;
B = A(ii);
or
B = A(sort(1:numel(A),'descend'));