[GRASS-user] Horizon step in r.sun

[Nikos Alexandris]

Hi list.

If I understand the theoretical background for r.sun, then, horizon 
maps are an option to speed up calculations. If this is true, this is 
not necessary when working in smaller regions (where memory and 
processing speed are simply enough).

In this case, r.sun's optional parameter "horizon_step" is only bound 
to an optionally defined horizon map. Wouldn't it make sense, then, to 
add another rule for this option, to warn a user that "horizon_step" 
serves for the "horizon_basename" option?  Something similar like the 
error message in r.sun's main.c:

--%<---
  607     }
  608     else if (useHorizonData()) {
  609     G_fatal_error(_("If you use the horizon option you must also 
set the 'horizonstep' parameter."));
  610     }
-->%---

Thanks for any explanations/comments in advance, Nikos