Aggregations in the fields panel

[hdsingh]

Implement feature in the fields panel to have aggregations like xr.mean().

[martindurant]

We will support the following options for dimensions which are not being used for plotting:

• max
• min
• mean
• stddev
• count (of non-nan)
• median
• select (this is currently the only option)

[hdsingh]

I have implemented these options:

• max
• min
• mean
• stddev
• median

on branch add_aggregate. Shall I wait for Pull Request #3 to merge before submitting this as PR?

I haven't been able to figure out what exactly to do with count (of non-nan), how to find and create graph for it. Can you please elaborate this? For the example dataset I tried

data.temp.count() - len(data.temp.isnull())

but I think this is not correct approach. Is count (of non-nan) supposed to be number which we can simply display?

[martindurant]

Count along dimension "time"

(~ data.temp.isnull()).sum(dim='time')

[martindurant]

The operator ~ is bit- or element-wise NOT in python.

[hdsingh]

Thanks!

[hdsingh]

Refer https://github.com/intake/xrviz/pull/4

[hdsingh]

The user can aggregate along remaining dimensions (not selected in x and y). The option to create a Select widget or Animate is also present in case the user does not wish to apply any aggregation on the dimension.