Several routines in the IMSL STAT LIBRARY have an option for printing results. These routines have an optional argument, IPRINT, to control the printing. In any routine that allows printing, if IPRINT = 0, (the default) then no printing is done (except possibly error messages). Some routines allow various amounts of printing; one value of IPRINT might result in printing only summary statistics, while another value might cause more detailed statistics or intermediate results to be printed. Other routines in the STAT LIBRARY do not print any of the results. In all routines, of course, the output is returned in FORTRAN variables, so if the routine does not do printing, or if you use the default IPRINT value, you can print the results yourself. The STAT LIBRARY contains some special routines just for printing arrays. For example, WRRRN and WRRRL are two convenient routines for printing matrices. See Chapter 19, “Utilities” for detailed descriptions of these routines.

A commonly used routine in the examples is the IMSL routine UMACH, which retrieves the FORTRAN device unit number for printing the results. Because this routine obtains device unit numbers, it can be used to redirect the input or output. The section on Machine-Dependent Constants in the Reference Material contains a description of the routine UMACH.