Frequently Asked Questions About Fortran

This is a GPF -centric (General Purpose Fortran) FAQ for Fortran.

Contents

• Gotchas:
  • Gotchas: Inheritance control for CONTAIN-ed procedures in Fortran
  • Gotchas: significant digits and simple assigns
  • Gotchas: conformance and elemental functions
  • Gotchas: avoiding allocatables
• Arrays:
  • How do I initialize an array in row-column order in Fortran?
  • Trouble initializing character arrays in Fortran; or why

    character(len=*),parameter :: array(*)=['one','two','three']

    is an error
  • "array=[]" will not work in Fortran
  • How do I compare arrays in Fortran?
• How does Fortran handle a scratch file?
• How do I put block comments in Fortran source?
• How do I get a file size in Fortran?
• Writing to stderr
• Automatically indenting a Fortran file
• How to issue a command to the operating system
• Build Tools
• Calling gnuplot(1) from Fortran
• Variable length CHARACTER arrays
• Non-advancing I/O
• Notes on list-directed output
• Notes on compound Boolean expressions
• Notes on including metadata in programs, objects, and source
• Procedure pointer
• Special values
• Leading space on list-directed output

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External Links

Fortran FAQs

• The Fortran Wiki FAQ
• The Fortran FAQ
• Fortran90.org FAQ
• pages.mtu.edu FAQ

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Fortran Compilers

• https://gcc.gnu.org/wiki/GFortran

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Repositories, Discussion Groups, Reference Sites, ...

• netlib mathematical algorithm repository
• The Fortran Wiki
• comp.lang.fortran newsgroup
• J3 Fortran Proposals
• GitHub site for Fortran feature proposals
• github list of open-source Fortran projects
• Fortran Wikibook

• Fortran Language Forum
• https://github.com/fortran-lang/fortran-lang.org
• Fortran Language Discourse
• Fortran Language Discourse YouTube
• Futility

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Fortran scientific model searches

XGC , SPECFEM , ACME , DIRAC , FLASH , GTC , LS-DALTON , NUCCOR , NWCHEM , RAPTOR , GAMESS(US) , GAMESS(UK) , Gaussian , VB2000 , XMVB , ACES , CFOUR , MOLPRO , MOLCAS ,

Economic Modeling

GEMPACK ,

Weather Modeling

WRF(Weather Research and Forecast),

Geography

geographiclib, fortranGIS,

Best Practices

• https://github.com/Fortran-FOSS-Programmers/BestPractices
• http://www.fortran.com/FortranStyle.pdf
• http://www.fortran90.org/src/best-practices.html
• http://research.metoffice.gov.uk/research/nwp/numerical/fortran90/f90standards.html
• https://github.com/szaghi/zen-of-fortran

Fortran document generators

fordocu , robodoc , ($)understand , doxygen ,

Repositories

• Trending Fortran on GitHub

Fortran and HPC searches

Fortran , Coarray , MPI , OpenMP , OpenACC , HDF5 , HPC , MPI-AMRVAC ,

Sites for gathering programming idioms and programming chrestomathy

• Rosetta Code (multi-lingual code samples)
• Fortran-specific Rosetta Code
• Exercism
• Programming-idioms
• codingame

Just found

• Simpson software
• The EDSS/Models-3 I/O API
• SimCom commericial services

Documentation

• lectures
• lectures<\a>

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