* IML Example;

* Show how to create a matrix from a dataset, 
  multiply two matrices with proc iml, and load 
  matrix columns into a dataset;

options linesize=70 nodate pageno=1 
   formchar = '|----|+|---+=|-/<>*';
data matrix_data;
   input s t;
   datalines;
2 -1
0  1
7  3
;

proc iml;

   * Hardcode matrix A;
   A = { 3  0  2,
         1  1  5 };
   print A;

   * Read data from matrix_data into B;
   use work.matrix_data;
   var_names = {'s', 't'};
   read all var var_names into B;
   close work.matrix_data;
   print B;

   * Multiply matrices A and B;
   C = A * B;
   print C;

   * Obtain columns of C;
   c1 = C[, 1];
   c2 = C[, 2];
   print c1 c2;

   * Create dataset from matrix C;
   create matrix_out var { c1 c2 };
   append;
   close matrix_out;

* Print dataset;
proc print data=matrix_out;

run;
quit;