Allow passing a default value (instead of ndarray) for data argument for DataArray #878
Description
Hi,
First of all, thanks a lot for the amazing module. It seems when I create a DataArray, I have to pass a numpy.ndarray with a correct size for the data argument. It works well when I already have some data, but sometimes I want to create an "empty" DataArray with known coordinates and fill up the data later. For these cases, it would be great if xarray allows passing just a value for the data argument, and fill up all the elements of the array with the value. For example, with pandas, I can do:
import pandas as pd
test = pd.DataFrame(data=.1, index=range(100), columns=['col1', 'col2'])and the resulting DataFrame would be:
col1 col2
0 0.1 0.1
1 0.1 0.1
2 0.1 0.1
.. ... ...
97 0.1 0.1
98 0.1 0.1
99 0.1 0.1
[100 rows x 2 columns]Thanks a lot!