test decoding num_dates in float types (#1863)
test decoding num_dates in float types (#1863)


jhamman/xarray,pydata/xarray,markelg/xray,shoyer/xarray,xray/xray,shoyer/xarray,shoyer/xray,markelg/xray,jhamman/xarray,pydata/xarray,chunweiyuan/xarray,jhamman/xarray,markelg/xray,pydata/xarray,jcmgray/xarray,jhamman/xray