topic Re: using IMSL fortran library in Software Archive

using IMSL fortran library

Intel_C_Intel — Wed, 06 Feb 2002 08:49:16 GMT

I am trying to solve a system of first order differential algebraic equations using the subroutine DASPG/DDASPG in IMSL library. To understand how this subroutine works, I copied the example code in the IMSL.PDF file and run the code in the window develop studio. The example is a simple Van der Pol equation and I was hoping to get the exact same results as in the example. But instead, I was prompted with error message: TERMINAL ERROR 7 from DD3SPG, which means the iteration matrix is singular. While the example code produced very smooth results. I wonder why the same exact code cannot reproduce the same results as the example did? Any insight would be greatly appreciated. Thanks

Re: using IMSL fortran library

sabalan — Wed, 06 Feb 2002 20:50:15 GMT

I copied the example into a console project and tried to compile and run it. There are several questions to answer before succeeding to run the example: Use "USE IMSL"? Comment "EXTERNAL DASPG, UMACH"? Have "IMSL.LIB" in Project | Settings | Link? Etc. It is also strange that I could compile and run the example in Release mode but I got 4 compiling errors in Debug mode telling "Error: The type of the actual argument differs from the type of the dummy argument. (and 3 other arguments)
CALL DASPG (N, T, T+DELT, IDO, Y, YPR, GCN)"
Anyway, the results I got in Release mode were 26.00000, 1.46302, -0.24098, -0.24220, -0.09071, which is not exactly the same as the results in the example documentation. (W2K-Pro SP2, PIII, CVF 6.6)

Sabalan.