Results obtained by matrix operations always a matrix files. Any matrix file can then be copied back to a data file by a FILE SAVE MAT <matrix_file> TO <data_file> operation (inverse for MAT SAVE DATA operation). Another (and more common) alternative is to let the matrix represent a linear mapping of existing variables in a data file. Then the LINCO operation for making linear combinations of variables should be used. L = LINCO (for linear combinations of variables) F = FILE SAVE MAT operation M = More information on multivariate analysis