MATLAB Central Newsreader - Please take a look at this code and let me know what's wrong

Please take a look at this code and let me know what's wrong

Mike M — Thu, 29 Oct 2009 05:55:04 -0400

Here's a "problem" I'm working on:
m = input('Enter an integer m to represent the number of desired rows:')
n = input('Enter an integer n to represent the number of desired columns:')
A = zeros(m:n);
for i = 1:m
    for j = 1:n
        A(i,j) = linspace((i-1)*n+1, (i-1)*n+j, n);
    end
end
A
It's supposed to create an m x n matrix that goes from 1:n by 1. In other words, if you enter 3 for m and 3 for n, you should get:
A = [1,2,3;4,5,6;7,8,9]. Entering 4 would do the same except to 16. I'm definitely a newbie so I'm not seeing the error.

Re: Please take a look at this code and let me know what's wrong

Nasser M. Abbasi — Thu, 29 Oct 2009 06:46:57 -0400

"Mike M" <mccain1976@gmail.com> wrote in message
news:hcbano$9kc$1@fred.mathworks.com...
> Here's a "problem" I'm working on:
> m = input('Enter an integer m to represent the number of desired rows:')
> n = input('Enter an integer n to represent the number of desired
> columns:')
> A = zeros(m:n);
> for i = 1:m
> for j = 1:n
> A(i,j) = linspace((i-1)*n+1, (i-1)*n+j, n);
> end
> end
> A
> It's supposed to create an m x n matrix that goes from 1:n by 1. In other
> words, if you enter 3 for m and 3 for n, you should get:
> A = [1,2,3;4,5,6;7,8,9]. Entering 4 would do the same except to 16. I'm
> definitely a newbie so I'm not seeing the error.

one way, use loop

m = input('Enter an integer m to represent the number of desired rows:')
n = input('Enter an integer n to represent the number of desired columns:')
A=zeros(m,n);

for i=1:m
    for j=1:n
         A(i,j)=n*(i-1)+j;
    end
end

(could be done witout loop if you really want to)

--Nasser

Re: Please take a look at this code and let me know what's wrong

Sebastian Arslanogullari — Wed, 04 Nov 2009 20:44:03 -0500

Hi Mike
As Nasser wrote, there are more elegant ways to solve this without a loop.
A one-line example would be:
A = shiftdim(reshape(1:m*n,n,m),1);

Regards
Sebastian Arslanogullari

"Mike M" <mccain1976@gmail.com> wrote in message <hcbano$9kc$1@fred.mathworks.com>...
> Here's a "problem" I'm working on:
> m = input('Enter an integer m to represent the number of desired rows:')
> n = input('Enter an integer n to represent the number of desired columns:')
> A = zeros(m:n);
> for i = 1:m
> for j = 1:n
> A(i,j) = linspace((i-1)*n+1, (i-1)*n+j, n);
> end
> end
> A
> It's supposed to create an m x n matrix that goes from 1:n by 1. In other words, if you enter 3 for m and 3 for n, you should get:
> A = [1,2,3;4,5,6;7,8,9]. Entering 4 would do the same except to 16. I'm definitely a newbie so I'm not seeing the error.