convert a double array to something like logical

Hello. I want to concert every

1-> 1 0 0 0 0 0 0

2-> 0 1 0 0 0 0 0

3-> 0 0 1 0 0 0 0

4-> 0 0 0 1 0 0 0

5-> 0 0 0 0 1 0 0

6-> 0 0 0 0 0 1 0

7-> 0 0 0 0 0 0 1

example: I have a vector A=[1;5;7;4]; I want it to be S= [

                                      1 0 0 0 0 0 0
                                      0 0 0 0 1 0 0
                                      0 0 0 0 0 0 1
                                      0 0 0 1 0 0 0];

Is it possible to do this without for loop? Thanks

Answer 1

[Azzi Abdelmalek]

A=[1;5;7;4];
B=zeros(numel(A),max(A))
B(sub2ind(size(B),(1:numel(A))',A))=1

Answer 2

[Vivek Selvam]

Hi Theodor,

You can try a look-up table like this:

lut = logical(diag(ones(1,7)));
A   = [1 5 7 4]';
S   = lut(A(:),:);

Answer 3

[hayim]

Late to the party, but how about this?

A = [1 5 7 4]';

S = bsxfun(@eq,A,1:7)

ans =

     1     0     0     0     0     0     0
     0     0     0     0     1     0     0
     0     0     0     0     0     0     1
     0     0     0     1     0     0     0

bsxfun is your friend!