Stream: python-questions

Topic: xesmf

view this post on Zulip Kate Hedstrom (Nov 06 2020 at 06:53):

I'm trying to use xesmf to regrid onto a curvilinear ROMS grid. It is telling me:

  File "/import/c1/AKWATERS/kate/.conda/envs/snowdrifts/lib/python3.7/site-packages/xesmf/frontend.py", line 94, in ds_to_ESMFlocstream
    raise ValueError("lon can only be 1d")
ValueError: lon can only be 1d

The test code:

import xarray as xr
import xesmf

def regrid_tracer(fld, method='bilinear'):
    coords = xr.open_dataset('/import/AKWATERS/kshedstrom/gridpak/Arctic2/grid_Arctic_4.nc')
    coords = coords.rename({'lon_rho': 'lon', 'lat_rho': 'lat'})
    gsource = xr.open_dataset('/import/AKWATERS/kshedstrom/HYCOM/Svalbard/data/HYCOM_GLBv0.08_2018_001.nc')

    regrid = xesmf.Regridder(
        gsource,
        coords,
        method=method,
        locstream_out=True,
        periodic=False,
        filename='regrid_t.nc',
        reuse_weights=True
    )
    tdest = regrid(gsource.ssh)
    return tdest

myssh = regrid_tracer('ssh')
myssh.to_netcdf('myssh.nc')

What am I doing wrong?

view this post on Zulip Matt Long (Nov 06 2020 at 16:27):

I wonder why ds_to_ESMFlocstream is involved. I would have expected an ESMF grid object. The locstream is indeed a 1D thing. I think xesmf must be getting confused and not instantiating an ESMF grid object from your data.
cc @geocat

view this post on Zulip Kate Hedstrom (Nov 06 2020 at 16:58):

Oh, I was copying from a code that had locstream set to true. It works without that. Thanks!

view this post on Zulip Matt Long (Nov 06 2020 at 16:59):

Ah, had I looked more closely at your code, I would have seen that. Glad it's working!

Last updated: May 16 2025 at 17:14 UTC