[GRASS-dev] isnan() in i.atcorr

[Glynn Clements]

Paul Kelly wrote:

> >> main.cpp includes <cmath>; I wonder if the problem is due to the fact
> >> isnan() is a C99 function? Should it be changed?
> >
> > Yes. This came up about a month ago:
> >
> > 	http://lists.osgeo.org/pipermail/grass-dev/2008-September/039910.html
> >
> > I thought it had been fixed already.
> 
> On closer inspection (and using a comment in the code as a hint), I think 
> i.atcorr is using isnan() where it wants to be using G_is_f_null_value(), 
> i.e. this:
> /* TODO: use G_set_f_null_value()?? */
>              if(vis && isnan(vis[col]) || alt && isnan(alt[col]) || isnan(buf[col])) {buf[col] = FP_NAN; continue;}
> should really be:
>              if(vis && G_is_f_null_value(&vis[col]) ||
>                 alt && G_is_f_null_value(&alt[col]) ||
>                 G_is_f_null_value(&buf[col]))
>              {
>                  G_set_f_null_value(&buf[col], 1);
>                  continue;
>              }
> 
> Any objections to me committing this?

None here.

FWIW, I've changed G_is_[fd]_null_value() to treat all NaNs as nulls,
not just the all-ones bit pattern.

-- 
Glynn Clements <glynn at gclements.plus.com>