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interfacing Lapack subroutine

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Pfor

Technical User
Aug 11, 2010
22
IT
Dear all,
I would like to interface a Lapack subroutine with my code.

There is a point I don't understand.
As far as I know in principle a f90
compiler should compile all the f77 codes,
however I have a problem with commented sentences.

When there is a * at the beginning of a line it is considered as commented if the extension of the file is .f,
(for example gvim turns it blue to show it is a comment)
while a error message is returned if the code is labelled as f90 (and gvim doesn't turn the line blue)

I am using gfortran as a compiler.

The lapack subroutine I would like to implement has a lot of * at the beginning.
Do you have any suggestion (I hope there is an option in the compiler to get rid of this problem but I can't find it)

thank you
cheers,
Paolo
 
Change the suffix of the source file : .f instead of .f90

Indeed, FORTRAN has two different formats :
- the fixed form which accepts several kinds of comments, in particular the * in column 1
- the free form which only accept the bang comment starting by ! (the rest of the line is a comment).

By default, a compiler considers that a source file with the suffix .f is in fixed format, and a source file with the suffix .f90 is a free format.
 
Thank you fot the hint;
however it doesn't work since I
have to interface a fixed format part of
a code (the Lapack subroutine for example) with a
free form one (my code).

I have been checking some converter like
the convert.f90 ; but so far I didn't succeed in
converting the form.

Do you have any suggestion?
cheers,
thank you
Paolo
 
Michael Metcalf's convert.f90 works for me -- how did you not succeed in converting the form?

--------------------------------------
Background: Chemical engineer, familiar mostly with MATLAB, but now branching out into real programming.
 
however it doesn't work since I
have to interface a fixed format part of
a code (the Lapack subroutine for example) with a
free form one (my code).

What do you mean by "interface" ? Why do you want to put Lapack code into sources files having the .f90 suffix ?

You can keep in the same time sources files in fixed format (with the suffix .f) and source files in free format (with suffix .f90). Both are valid FORTRAN-90 source files !

To compile and link with gfortran :

Code:
gfortran *.f *.f90
 
Thank you all for your answers.

I tried to use "convert.f90" but at some point there
was a error message:

>At line 953 of file convert.f90
>Fortran runtime error: Bad value during integer read

I figured out that the problem is in the fortran file to be converted.

If I open it with gvim editor at the beginning of the "problematic" line there are some spaces whose color is red, and this jams the convert.f90.

I am trying to get rid of these "red spacess".

Regarding the idea of compiling a subroutine without writing it in the main code...I have never done this procedure, I will try it,
thank you,
cheers
Paolo

 
Those red spaces in gvim are TAB character(s). Just replace it with the appropriate number of spaces.

--------------------------------------
Background: Chemical engineer, familiar mostly with MATLAB, but now branching out into real programming.
 
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