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29285 Discussions

Select case block vs array of function pointers

FilippoMonari
Beginner
‎12-13-2020 12:31 PM
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Hi all, 

I would like some advice about the following. I have a quite big SELECT CASE block where cases are unique integers. The block includes about 200 cases representing different functions. I was wondering if I could get any benefit in terms of speed by replacing the big SELECT CASE block with an array pointers pointing to functions to apply. Thanks in advance.

Regards,

Filippo

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JohnNichols
Valued Contributor III
‎12-13-2020 01:22 PM
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Pick the one that is easy to maintain - although 200 seems a lot 

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FortranFan
Honored Contributor III
‎12-13-2020 01:24 PM
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@FilippoMonari ,

Since your question is general Fortran, you may want to consider posting it at Fortran Discourse site (and possibly also USENET based comp.lang.fortran) for wider feedback: 

By the way, here's a long thread toward a similar discussion at comp.lang.fortran a while ago that may help you with some pointers:  https://groups.google.com/g/comp.lang.fortran/c/6uROcAIvPcQ/m/ULl1Muz0CAAJ

Ultimately I think you'll have to figure out what works best for you.

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FortranFan
Honored Contributor III
‎12-13-2020 01:25 PM
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In response to FortranFan

Link to Fortran Discourse site: https://fortran-lang.discourse.group/

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