[GRASS-user] r.terraflow: dcell low precision?

GRASS GRASS user
1

   Starting r.terraflow produces this warning:

WARNING: raster aber5m is of type DCELL_TYPE --precision may be lost.

   My understanding is that raster maps have three possible data types:
integer (cell), floating point single-precision (fcell), and floating point
double precision (dcell). If my understanding is correct then I don't get
the warning.

   Explanation, please.

Rich

2

Rich Shepard wrote:

  Starting r.terraflow produces this warning:

WARNING: raster aber5m is of type DCELL_TYPE --precision may be lost.

  My understanding is that raster maps have three possible data types:
integer (cell), floating point single-precision (fcell), and floating point
double precision (dcell). If my understanding is correct then I don't get
the warning.

  Explanation, please.

r.terraflow stores elevation internally as floating-point single precision which is more than enough if elevation is in meters or feet so you can safely ignore the warning.

3

On Wed, 10 Feb 2010, Markus Metz wrote:

r.terraflow stores elevation internally as floating-point single precision
which is more than enough if elevation is in meters or feet so you can
safely ignore the warning.

Markus,

   Thank you. Perhaps that warning ought to be taken out of the code since it
is not applicable.

Rich