Can't write Float16 data cubes

[ayushpatnaikgit]

Can't write a data cube which has Float16 values.

raster = Raster("test.nc")
raster = Float16.(raster)
write("test.nc", raster) # doesn't work

ERROR: Your data is not a type that netcdf can store

While there are no issues if I convert it to Float32 and then write.

raster = Float32.(raster)
write("test.nc", raster)  # this works

Also no issues if I convert it to Float64 and then write.

raster = Float64.(raster)
write("test.nc", raster)  # this works

I used this netCDF file for testing. It's called mumbai_radiance.nc instead of test.nc

[rafaqz]

NetCDF doesn't support Float16. But maybe we should silently convert to Float32?

Xarray seemed to decide it was best to make the user do that manually:
pydata/xarray#1877

But we could make the error message clearer? Another option is to convert to Float32 but print a @warning message so the user is aware that is happening.

[ayushpatnaikgit]

I also think that it's best for the user to convert it manually, and it can be suggested in the error message. Perhaps something like:

if typeof(raster[1]) == Float16
@error "NetCDF doesn't support Float16, convert your variable Float32.