Creating a new matrix basd on the index and value of an existing matrix

Hi all,

I am new to matlab and I need your help on this.

I have a m x n matrix and I want to create a new m*n x 3 matrix in which the third column is the value from first matrix and the first two columns are the corresponding index of the value. For example, if the first matrix is [0.001 0.002 0.003 0.004; 0.005 0.006 0.007 0.008], I would like to make a matrix as [1 1 0.001; 1 2 0.002; 1 3 0.003; 1 4 0.004; 2 1 0.005; 2 2 0.006; 2 3 0.007; 2 4 0.008].

So how can I create the second matrix based on the index and value of first matrix?

Thanks in advance.

Answer 1

[Kumar Pallav]

You could try the following code in matlab to get the desired result:

input=[0.001 0.002 0.003 0.004; 0.005 0.006 0.007 0.008];
[nrows ncols]=size(input); %stores the number of rows and columns in input
values=[]; %output matrix
for r=1:nrows
    for c=1:ncols
        values=[values;r c input(r,c)];% keep appending [r,c,input] to new columns
    end
end
disp(values); %display the output

Hope this helps!

[Rong Sun]

Thanks, Kumar!