How do I use fprintf to show the entire array in one ouput statement

>>

A = [-4 2 -7 6 8; 4 -5 8 -1 0; 0 -4 3 1 10; -8 7 -10 5 -2];

[rows cols] = size(A);

Z = zeros(size(A));

for x = 1:1:rows

    for y = 1:1:cols
        if A(x,y) <= 4
            Z(x,y) = A(x,y);
        end
    end
end

fprintf('%i\n',Z);

My ouput statement I am getting is

   -4
         4
   0
  -8
   2
  -5
  -4
   0
  -7
   0
   3
  -10
   0
  -1
   1
   0
   0
   0
   0
  -2

Instead of

                         -4   2 -7   0  0

                          4  -5  0  -1  0   

                          0  -4  3   1  0

                         -8   0 -10  0 -2

Answer 1

[Jan]

fprintf('%i %i %i %i %i\n', Z.');

or:

fprintf('%4i %4i %4i %4i %4i\n', Z.');

Note that the matrix must be transposed, because the elements are store columnwise, but the display is written in rowwise order.

By the way: It is easier without loops:

Z        = zeros(size(A));
index    = (A <= 4);
Z(index) = A(index);

Or:

Z        = A;
Z(Z > 4) = 0;

[Josua Mensah]

Thanks man. Was not even aware of the other ways to go about it.

Answer 2

[Jay Stanley]

Tunc Durmaz,

If you do not know the dimension of your array you can get its size and replicate a template based on those dimensions

Here's a minimum working example

matrix = magic(4) % example matrix
[mrows, ncols] = size(matrix)
outputstr = ['%' num2str(mrows) 'i '] % template for the string, you put your datatype here
outputstr = repmat(outputstr, 1, ncols) % replicate it to match the number of columns
outputstr = [outputstr '\n'] % add a new line if you want
fprintf(outputstr, matrix.') % write it

For completeness sake there is another trivial solution that does not use repmat via the loop

matrix = magic(4) % example matrix
[mrows, ncols] = size(matrix)
outputstr = ['%' num2str(mrows) 'i ']
template = ['%' num2str(mrows) 'i '] % template for the string, you put your datatype here
outputstr = template
for i = 2:mcols
    outputstr = [outputstr template]
end
outputstr = [outputstr '\n'] % add a new line if you want
fprintf(outputstr, matrix.') % write it

[Tunc Durmaz]

That was very helpful, thanks!

Answer 3

[Tunc Durmaz]

What if we do not know the dimension of Z? Any way to address this in fprintf?

Cheers,