Utilities

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  • Utilities are used to manipulate or analyse data, either during runtime or in the post-processing phase.
  • Some of the utilities are non-specific to pipe flow, e.g. code for the GMRES algorithm.
  • Almost all modifications can/should be made via a utility, rather than altering the core code (i.e. avoid editing the contents of the program/ directory wherever possible).
  • Utilities are kept in utils/.


Building

To build, in Makefile, set UTIL = utilname (omitting the .f90 extension), then type

> make
> make install
> make util
> mv utilname.out ...

The penultimate command creates utilname.out.

It is good practice to do a 'make install' to generate a main.info file to keep alongside the executable.

Pre/post-processing

Runtime processing

Non-problem-specific codes

  • These are designed for integration with any pre-existing code.
  • File:Arnoldi.f - Krylov-subspace method for calculating eigenvalues of a matrix.
  • File:GMRESm.f90 - Krylov-subspace method for solving the linear system Ax=b for x.
  • File:NewtonHook.f90 - Newton-hookstep method for finding nonlinear solutions x for F(x)=0.