How do I Transpose a multi dimensional array?

Question

I think this might be a pretty simple question, but I haven't been able to figure it out yet. If I've got a 2-dimensional array like so:

int[,] matris = new int[5, 8] { 
       { 1, 2, 3, 4, 5,6,7,8 }, 
       {9,10,11,12,13,14,15,16},
       { 17,18,19,20,21,22,23,24 },
       { 25,26,27,28,29,30,31,32 },
       { 33,34,35,36,37,38,39,40 },

        };

and a for loop, like this:

  for (int r = 0; r < 5; r++)
        {

            for (int j = 0; j < 8; j++)
                Console.Write("{0} ", matris[r, j]);

            Console.WriteLine();
        }

So with this code I am printing out the multi dimensional array. But how do I print out a transpose of the array?

What do you mean by "transponent"? It's not a term I've come across before. — Jon Skeet, Aug 21 '13 at 22:17
Perhaps he means transpose? http://en.wikipedia.org/wiki/Transpose — Colin Basnett, Aug 21 '13 at 22:18
See also: http://stackoverflow.com/a/2893367/2630934 They talk about multi dimensional arrays, but to transpose an array of [x,y], you just have to make a new array with dimensions [y,x] and assign to each individual value accordingly. — User, Aug 21 '13 at 22:33

MarcinJuraszek · Answer 1 · 2013-08-21T22:33:53.640

18

Just change your loops with each other:

for (int j = 0; j < 8; j++)
{
    for (int r = 0; r < 5; r++)
        Console.Write("{0} ", matris[r, j]);

    Console.WriteLine();
}

Creating new array:

var newArray = new int[8, 5];
for (int j = 0; j < 8; j++)
    for (int r = 0; r < 5; r++)
        newArray[j, r] = matris[r, j];

edited Aug 21 '13 at 22:33

answered Aug 21 '13 at 22:20

MarcinJuraszek

124,003
15
196
263

yeeah ok now I see what I did wrong.. But if I want to save the transpose matris into an new array? – user2669196 Aug 21 '13 at 22:24

score 10 · Answer 2 · answered Aug 21 '13 at 22:25

10

You just need to do this:

for (int r = 0; r < 8; r++)
{
    for (int j = 0; j < 5; j++)
        Console.Write("{0} ", matris[j, r]);
    Console.WriteLine();
}

answered Aug 21 '13 at 22:25

Anna

538
2
4
13

oh, posted too late! It's pretty much the same solution that @MarcinJuraszek posted :) – Anna Aug 21 '13 at 22:26
I would say this is the right answer. People just rush into up-voting. – ataravati Aug 21 '13 at 22:28
@ataravati It's exactly the same as mine :) Just variables names replaced. – MarcinJuraszek Aug 21 '13 at 22:34
@MarcinJuraszek It is exactly the same, but you have switched the variables in the original question, which may give the wrong impression (to the beginners) that two sets of loops are required to achieve this. And, your comment is actually misleading too. – ataravati Aug 21 '13 at 22:39

How do I Transpose a multi dimensional array?

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