html_url,issue_url,id,node_id,user,created_at,updated_at,author_association,body,reactions,performed_via_github_app,issue https://github.com/pydata/xarray/issues/1064#issuecomment-359839979,https://api.github.com/repos/pydata/xarray/issues/1064,359839979,MDEyOklzc3VlQ29tbWVudDM1OTgzOTk3OQ==,1997005,2018-01-23T16:07:44Z,2018-01-23T16:07:44Z,CONTRIBUTOR,"FYI, `merged.time.encoding = {}` before calling `to_netcdf` seems to avoid the RuntimeWarning.","{""total_count"": 2, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 1, ""rocket"": 0, ""eyes"": 0}",,185709414 https://github.com/pydata/xarray/issues/1064#issuecomment-358570582,https://api.github.com/repos/pydata/xarray/issues/1064,358570582,MDEyOklzc3VlQ29tbWVudDM1ODU3MDU4Mg==,1997005,2018-01-18T08:16:06Z,2018-01-18T08:16:06Z,CONTRIBUTOR,"There you go ! ```python import numpy import pandas import tempfile import warnings import xarray array1 = xarray.DataArray( numpy.random.rand(5), dims=['time'], coords={'time': pandas.to_datetime(['2018-01-01', '2018-01-01 00:01', '2018-01-01 00:02', '2018-01-01 00:03', '2018-01-01 00:04'])}, name='foo' ) array2 = xarray.DataArray( numpy.random.rand(5), dims=['time'], coords={'time': pandas.to_datetime(['2018-01-01 00:05', '2018-01-01 00:05:10', '2018-01-01 00:05:20', '2018-01-01 00:05:30', '2018-01-01 00:05:40'])}, name='foo' ) with tempfile.NamedTemporaryFile() as tmp: # save first array array1.to_netcdf(tmp.name) # reload it array1_reloaded = xarray.open_dataarray(tmp.name) # the time encoding stores minutes as int, so seconds won't be allowed at next call of to_netcdf assert array1_reloaded.time.encoding['dtype'] == numpy.int64 assert array1_reloaded.time.encoding['units'] == 'minutes since 2018-01-01 00:00:00' merged = xarray.merge([array1_reloaded, array2]) array1_reloaded.close() with warnings.catch_warnings(): warnings.filterwarnings('error', category=RuntimeWarning) merged.to_netcdf(tmp.name) ``` ","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,185709414 https://github.com/pydata/xarray/issues/1064#issuecomment-358454214,https://api.github.com/repos/pydata/xarray/issues/1064,358454214,MDEyOklzc3VlQ29tbWVudDM1ODQ1NDIxNA==,1217238,2018-01-17T21:34:13Z,2018-01-17T21:34:13Z,MEMBER,"@NotSqrt can you make a minimum working example for this? e.g., a netCDF file with problematic data, and associated code that writes a netCDF file with lost time resolution. That would really help us diagnose and solve this problem.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,185709414 https://github.com/pydata/xarray/issues/1064#issuecomment-358324488,https://api.github.com/repos/pydata/xarray/issues/1064,358324488,MDEyOklzc3VlQ29tbWVudDM1ODMyNDQ4OA==,1997005,2018-01-17T14:41:14Z,2018-01-17T14:41:14Z,CONTRIBUTOR,"I faced this issue when switching from a ``concat`` to a ``merge``. The first merged dataset had a time dimension which ``encoding`` says ``{'calendar': 'proleptic_gregorian', 'dtype': dtype('int64'), 'units': 'minutes since 2017-08-20 00:00:00'}``, which meant that the data from the second merged dataset could not be stored with a finer resolution than minutes. If I try to store values like '2017-08-20 00:00:30', I get the warning `xarray\conventions.py:1092: RuntimeWarning: saving variable time with floating point data as an integer dtype without any _FillValue to use for NaNs`. Maybe it is similar in your case: netcdf stored the data as 'hours since XXXX', so you lose the minutes. ","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,185709414 https://github.com/pydata/xarray/issues/1064#issuecomment-261004033,https://api.github.com/repos/pydata/xarray/issues/1064,261004033,MDEyOklzc3VlQ29tbWVudDI2MTAwNDAzMw==,16919188,2016-11-16T16:57:21Z,2016-11-16T16:57:21Z,NONE,"@jhamman Here my example file ftp://ftp.irsn.fr/argon/Example ","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,185709414 https://github.com/pydata/xarray/issues/1064#issuecomment-260994864,https://api.github.com/repos/pydata/xarray/issues/1064,260994864,MDEyOklzc3VlQ29tbWVudDI2MDk5NDg2NA==,16919188,2016-11-16T16:29:32Z,2016-11-16T16:29:32Z,NONE,"This is the warning I got when I wrote on my file with ""to_necdf()"" xarray\conventions.py:1060: RuntimeWarning: saving variable time with floating point data as an integer dtype without any _FillValue to use for NaNs for k, v in iteritems(variables)) @jhamman It's seems than the error appears only with a variable ""rain"" who commes from a previous created netcdf file, but I will try to provide you an example. tanks ","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,185709414 https://github.com/pydata/xarray/issues/1064#issuecomment-257053396,https://api.github.com/repos/pydata/xarray/issues/1064,257053396,MDEyOklzc3VlQ29tbWVudDI1NzA1MzM5Ng==,2443309,2016-10-28T23:38:46Z,2016-10-28T23:38:46Z,MEMBER,"@Scheibs - thanks for the report. Can you provide a simple, minimum working example ([MWE](https://en.wikipedia.org/wiki/Minimal_Working_Example))? ","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,185709414