Transformer for dropping NAs only

[TeoSkondras]

Is there any transformer that can drop all the NA values in a column or in the entire dataframe, without having to modify it?

[fkiraly]

There is a generic pandas adapter which allows to add any pandas method as an sktime transformer step:

from sktime.transformations.series.adapt import PandasTransformAdaptor

In your case you would probably pick method="dropna"

[TeoSkondras]

Thank you, that worked!

[hliebert]

I've recently used this and found it to work only as the last transformer in a pipeline.

[fkiraly]

??? That sounds like a bug, @hliebert! Would be much appreciated if you could kindly report it, with a minimal failing example?

[hliebert]

Reported here: #4977. I wanted to reproduce it first, it only occured in conjunction with IndexSubset.

[TeoSkondras]

Another thing with PandasTransformAdaptor is that it does not support the invert_transform.
NotImplementedError: <class 'sktime.transformations.series.adapt.PandasTransformAdaptor'> does not implement inverse_transform

[fkiraly]

I thought it does? If the wrapped trafo has it, the PandasTransformAdaptor also has it.

Can you report an example?