Matlab - Matriz

clear

 A=[ 1     4     7    10

     2     5    8    11

     3     6    9    12]

 for i=1:size(A,2)

     C(i:i+2,i)=A(:,i);

 end

 C

>> matrizz2

A =

     1     4     7    10

     2     5     8    11

     3     6     9    12

C =

     1     0     0     0

     2     4     0     0

     3     5     7     0

     0     6     8    10

     0     0     9    11

     0     0     0    12