Data Type

Integer

Default Value

2

Description

This parameter controls the amount of printed output produced by calls to the vector solution routine RSDS, RNDS, CHDS, CSDS, CNDS. The print code summary table lists the values of IPRS and the output produced.

The following is a detailed description of each option. The value of IPRS you specify is obtained by adding together the numeric value of each option you select. Because these numeric values are a power of 2, they have the effect of setting bits in IPRS.

  • 0, No output from vector solution is printed.
  • +1, Start and stop timing is printed.
    The following is an example: 
     START OF FMS VECTOR SOLUTION
 END   OF FMS VECTOR SOLUTION.
 TIME(SEC): CPU   =       4.301,        WALL=       4.651
  • +2, Timing information for each vector group is printed.
    The following is an example: 
     F M S     V E C T O R     S O L U T I O N
 <----FUNCTION--->   <--VECTORS-->     <-CPU  TIME(SEC)->     <-WALL TIME(SEC)->
                     FIRST    LAST     DELTA        TOTAL     DELTA        TOTAL
 FORWARD REDUCTION       1      51     0.845        0.845     0.974        0.974
 DIAGONAL  SCALING       1      51     0.017        0.862     0.030        1.004
 BACK-SUBSTITUTION       1      51     0.803        1.665     0.820        1.824
 FORWARD REDUCTION      52     100     1.370        3.035     3.578        5.403
 DIAGONAL  SCALING      52     100     0.016        3.051     0.029        5.432
 BACK-SUBSTITUTION      52     100     0.792        3.842     0.807        6.239
  • +4, Right-hand side vectors {RHS} are printed before forward reduction.
  • +8, Right-hand side vectors are printed after they have been reduced by the lower triangle factor [L]-1{RHS}.
  • +16, The reduced vectors are printed after diagonal scaling [1/D][L]-1{RHS} (symmetric matrices only).
  • +32, The solution vectors {SOL} are printed after back-substitution.
  • +128, The diagonal factor reciprocals [1/D] are printed.
  • +512, The lower triangle factor [L] and upper triangle factor [U] (nonsymmetric) are printed.
  • +1024, The actual performance achieved in Megaflops is printed. This computation is based on an actual count of the number of floating point operations (adds and multiplies) required and the actual time spent.
    NOTE: The operation count may take some time. Therefore this option is not recommended as a default for production applications. It is provided for application tuning.

CAUTION: For large problems this parameter can produce a lot of output. You can use the FMS Parameters NEQPR1 and NEQPR2 to create a window on the matrix and vector terms printed.