Language Reference

DESIGNF Function

creates a full-rank design matrix

DESIGNF( column-vector)

where column-vector is a numeric column vector or literal.

The DESIGNF function works like the DESIGN function; however, the result matrix is one column smaller and can be used to produce full-rank design matrices. The result of the DESIGNF function is the same as if you took the last column off the DESIGN function result and subtracted it from the other columns of the result.

For example, consider the following statements:

  
    a={1,1,2,2,3,3}; 
    b=designf(a);
 

These statements produce the following design matrix:

  
              B             6 rows      2 cols    (numeric) 
  
                                   1         0 
                                   1         0 
                                   0         1 
                                   0         1 
                                  -1        -1 
                                  -1        -1