R help - Oct 2005 - passing char to Fortran routine

Hello all,

I am using an existing Fortran routine that takes a single character string
as argument. The routine echoes the argument that I provide. When working on
OS X 3.9 there seems to be no problem, ie the Fortran routine nicely echoes
my argument. However, I compiled the same package on a PC (using all the
tools provided in the R for windows faq), and the routine only echoes the
first letter of each character string that I pass on to it.

My questions are: 
1) Is this somehow compiler specific?
2) Should I explicitly provide the Fortran routine with the length of the
character string? 
3) I am at a loss as to what is happening here, so any hint is welcome (-;

The call to the Fortran routine is as follows:

.Fortran("npoptn",as.character(opt),PACKAGE="depmix")

where opt is a character string such as opt="Iteration limit = 100"

best, ingmar

> PLEASE do read the posting guide! 
http://www.R-project.org/posting-guide.html

Programming questions are appropriate for R-devel, as it says there.

The issue is OS-specific, but we don't see what your Fortran code is.
If you send a reproducible example to the R-devel list, people may be able 
to suggest what the problem is.

On Mon, 10 Oct 2005, Ingmar Visser wrote:
> Hello all,
>
> I am using an existing Fortran routine that takes a single character string
> as argument. The routine echoes the argument that I provide. When working
on
> OS X 3.9 there seems to be no problem, ie the Fortran routine nicely echoes
> my argument. However, I compiled the same package on a PC (using all the
> tools provided in the R for windows faq), and the routine only echoes the
> first letter of each character string that I pass on to it.
>
> My questions are:
> 1) Is this somehow compiler specific?
> 2) Should I explicitly provide the Fortran routine with the length of the
> character string?
> 3) I am at a loss as to what is happening here, so any hint is welcome (-;
>
> The call to the Fortran routine is as follows:
>
> .Fortran("npoptn",as.character(opt),PACKAGE="depmix")
>
> where opt is a character string such as opt="Iteration limit =
100"
-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
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