Probabilistic Specification of Metocean Criteria:
Generating and Searching N-Year Contours for Extreme Response Estimation
The HTCNTR, IFORM, and SURFIT Routines (Report RMS-32)
The source code file contains, in zipped format, files associated with the release of the HTCNTR routine. This is part of a suite of programs (HTCNTR, IFORM, SURFIT) that constructs and searches N-year contours of (Hs, Tp) seastate characteristics at different locations.
IFORM is the most general of these programs. It both constructs the N-year contour, and searches it for the maximum value of an arbitrary response. As in standard FORM methods, the response is characterized probabilistically through a user-defined g-function subroutine.
Method: Inverse FORM.
Documentation: RMS Report 32
Subdirectories:
src contains all FORTRAN source code *.f
example contains output files crest.* from extreme crest example (see Documentation)
To Compile: Compile and link all *.f (FORTRAN) files in subdirectory src, create executable file crest.x
Usage: crest.x < crest.in > crest.out
This will run the example extreme crest problem. The input file crest.in should be taken from the examples directory. Output will be stored in crest.out and crest.log; these files should compare (within numerical noise) to the results in the example directory.
Status: Iform has been recompiled on a Mac using the public domain compiler GNU FORTRAN (see crest.cmp and crest.x in src). It was found necessary to make several modifications in the source code file tn3.f -- see calls to the subroutine hypot( ). Results from the example directory (crest.*) have been confirmed within numerical noise.
Steve Winterstein
2011