issue_comments: 493431087

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https://github.com/pydata/xarray/issues/2278#issuecomment-493431087 https://api.github.com/repos/pydata/xarray/issues/2278 493431087 MDEyOklzc3VlQ29tbWVudDQ5MzQzMTA4Nw== 46813815 2019-05-17T12:11:21Z 2019-05-17T14:03:38Z NONE

Hi, second test case indicated by Apatlpo on on 12 Jul 2018, brakes ```python nx, ny, nt = 32, 32, 64 ds = xr.Dataset({}, coords={'x':np.arange(nx),'y':np.arange(ny), 't': np.arange(nt)}) ds = ds.assign(v=ds.tnp.cos(np.pi/180./100ds.x)np.cos(np.pi/180./50ds.y)) ds = ds.chunk({'t': 1, 'x': nx/2, 'y': ny/2}) ds.to_zarr('data.zarr', mode='w')

```

python ds = xr.open_zarr('data.zarr') ds = ds.chunk({'t': nt, 'x': nx/4, 'y': ny/4}) ds.to_zarr('data_rechunked.zarr', mode='w')

Err message is following . ValueError: Final chunk of Zarr array must be the same size or smaller than the first. The specified Zarr chunk encoding is (1, 16, 16), but (64,) in variable Dask chunks ((64,), (8, 8, 8, 8), (8, 8, 8, 8)) is incompatible. Consider rechunking using `chunk()

(if I add del ds.v.encoding['chunks'] as follows, it does not break) python nx, ny, nt = 32, 32, 64 ds = xr.Dataset({}, coords={'x':np.arange(nx),'y':np.arange(ny), 't': np.arange(nt)}) ds = ds.assign(v=ds.t*np.cos(np.pi/180./100*ds.x)*np.cos(np.pi/180./50*ds.y)) ds = ds.chunk({'t': 1, 'x': nx/2, 'y': ny/2}) ds.to_zarr('data.zarr', mode='w') ds = xr.open_zarr('data.zarr') del ds.v.encoding['chunks'] ds = ds.chunk({'t': nt, 'x': nx/4, 'y': ny/4}) ds.to_zarr('data_rechunked.zarr', mode='w')

 
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