[GRASS-user] Do not report cells where thousands of maps have no data

[Nikos Alexandris]

GRASS GIS' `r.stats` modules does this:
```
r.stats input=$(g.list rast pattern=cru*.*1 separator=comma) -n -x -N
```

However, it won't do it for thousands of maps. Too many maps will hit
the '[Argument list too long]' error which is triggered by the ARG_MAX
constant.  Is there a work-around?

Else, I see no option but to set on a Python script that will loop over
thousands of maps and will identify pixels for which all maps have a
valid value.  Any recommendations (like best to user xarray or numpy or
rasterio or else...)?

Thank you, Nikos