how to generate the matrix of (50,100) with its diagonal alone having values

how to generate the matrix of (50,100) with its diagonal alone having values

Answer 1

[Stephen23]

Method one: indexing:

M = zeros(50,100);
M(1:51:50^2) = V % vector V must have 50 elements

A simple example:

>> M = zeros(5,10);
>> M(1:6:25) = 1:5
M =
   1   0   0   0   0   0   0   0   0   0
   0   2   0   0   0   0   0   0   0   0
   0   0   3   0   0   0   0   0   0   0
   0   0   0   4   0   0   0   0   0   0
   0   0   0   0   5   0   0   0   0   0

Method two: diag:

[diag(V),zeros(50)] % vector V has 50 elements

and an example:

>> [diag(1:5),zeros(5)]
ans =
   1   0   0   0   0   0   0   0   0   0
   0   2   0   0   0   0   0   0   0   0
   0   0   3   0   0   0   0   0   0   0
   0   0   0   4   0   0   0   0   0   0
   0   0   0   0   5   0   0   0   0   0

[Prabha Kumaresan]

ok.But it displays diagonal values till 5 columns and it remains zero for the rest of the 5 columns.could you tell me how to display the values for the rest of the 5 columns in the diagonal manner.

[Stephen23]

@Prabha Kumaresan: Your original question asked for a matrix with "with its diagonal alone having values". Now you have described something else, something which apparently is not a diagonal matrix at all.

Perhaps what you want can be made using two diagonal matrices:

>> [diag(1:5),diag(6:10)]
ans =
    1    0    0    0    0    6    0    0    0    0
    0    2    0    0    0    0    7    0    0    0
    0    0    3    0    0    0    0    8    0    0
    0    0    0    4    0    0    0    0    9    0
    0    0    0    0    5    0    0    0    0   10

Is that what you are after? If not, please show an illustrative example of what you are trying to do.

[Prabha Kumaresan]

thanks this was the result i expected.

[Stephen23]

@Prabha Kumaresan: if this is what you need then please remember to accept the answer that helps you most. We are volunteers, and accepting is the easiest way for you to show your appreciation for their time spent helping you.