How do I preserve dimension values in xarray when using isel?

user_5671548 0
Viewed 918

The setup:

I have an xarray dataset with dimensions x,y,t called foo

the selection command 

bar = foo.isel(t = 2)

selects a single slice along the t axis and stores the results in bar

My Issue:
bar only has dimensions x,y

I would like to use t after the selection for quick recombination of many slices

Expectation:
bar has dimensions x,y,t (The same dimensions as its superset)

  • Each individual slice of foo has an associated t coordinate value in a real world setting. An individual slice bar from foo should preserve that t coordinate so that if a dataset was split for whatever reason, it can be recombined in the future.

  • Predictable/consistent behaviour regarding sel's or isel's treatment of dimension would mean less manual checking.

Questions

(1) The documentation references a kwarg called **indexers_kwargs. Is there more specific documentation on what is accepted under **indexers_kwargs? I'm having trouble finding the definitive list or a definition that makes sense. My hopes are that there may exist a kwarg used to preserve the t value when using sel or isel. Does such a thing exist?

(2) Currently the approach I'm considering is wrapping isel or sel with a function that can preserve dims with only one value. Would be much happier if it were natively supported. Can you imagine/propose an alternative workaround?

python-xarray python-3.x
1 Answers

Current solutions that preserve dimensions:

isel using list 

bar = foo.isel( t = [2] )

isel using slice

bar = foo.isel( t = slice(2, 2 + 1) )
user_56715480
Related