add new constraint on zoom definition

[arsouze]

I would like to be able to define in XIOS a zoom based on a mask. Typically, I would like to be able to compute a mean (and time series) of temperature over the Atlantic basin, based on an Atlantic mask definition provided as an input file.
I think this goes beyond the (i,j) or (lon,lat) zooming options available so far.

[ymipsl]

This new functionnality would be added by developping spatial reduce filters. This family of filters would be able to reduce data on a global grid by different reduce operation (sum, max, min, etc...). For example a 2d domain can be reduces in 1d axis (partial reduction along one direction) or scalars (global recution). Mask of the grid would be taken into account to supress the contribution of masked cells.

Would this functionnality be convenient for your requierement ?

Delay for this would be arround 2-3 months because some other stuff planed have an higher priority.

[ymipsl]

Implemented in XIOS_DEV_CMIP6.