Removing columns where every value is empty

The RDKit R-group decomposition node generates a lot of empty columns (empty = every cell contains a missing value). I would like to be able to filter these columns out so that the results are easier to work with.

I'm pretty sure I have already seen a node to do this, but I cannot find it.

Any suggestions?

-greg

You should be able to transpose the table, then use Row Filter, then Choose Missing Value Match, and then on the left panel choose Exclude by Attribute. Then transpose back.

I hope this is what you are looking for.

That's rather a lot of work for what is fundamentally a fairly simple operation. Would be nice to have something more straightforward.

-greg

this looks like a very old question, but I run into a similar problem,

I have a large table, with many columns, in these columns many fields are empty, but if there is at least one real value, I would like to keep such a column.
I only want to remove columns that are entirely empty … is there a solution by now?

transposing etc did not work in my described case, as I then also would remove columns that I still want to keep.

best regards,
Jan

Hi @j_wollenhaupt , I don’t know if there are other shorter variants of this, or whether this will work ok with a large data set, but it may be of assistance

Remove Empty Columns.knwf (22.1 KB)

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@j_wollenhaupt, I think that the Missing Value Column Filter node is the way to go. Just set the threshold to 100%.

Using the data that @takbb generated:

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wow, @takbb @elsamuel … these answers were really fast and both solutions work perfectly…

how could I miss this Missing Value Column Filter node? :slight_smile:

thank you so much!

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Hi @j_wollenhaupt, I was thinking the same thing about how I missed that node… :joy: But it was fun. There’s another node that might be worth a look too for similar use cases… I’ve not tried it out but it’s the Constant Value Column Filter

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very nice @elsamuel
keep it simple. I was thinking about column loop so way to complex. That’s exactly why it is so interesting to see other solutions here
br

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