Deleting all keys that have null values

I have a notebook that I am working on that starts with an imported CSV file. Many of the rows have blank data in them. I have used the following command to establish a list of associations:

test = AssociationThread[First[rawdata] -> #] & /@ Rest[rawdata]


The InputForm of the above code produces an end result that is something like this:

InputForm

test = >, <


I want to remove the associations that have blank values so my end result would be more like this:

test2 = <


Is there a simple way to drop all keys across all the entries that have null values? I have looked into KeyDrop / KeyDropFrom but can't figure out a way to drop a key based on its value.

KeyDrop

KeyDropFrom

Based on this thread, I am thinking there may be a way to use Position or PositionIndex.

Position

PositionIndex

Thoughts?

2 Answers
2

Try this:

DeleteCases[test, "", 2]


>

Since this is about a list of associations, the level on which to search the pattern "" is level 2 (only), therefore the 2 as third argument.

""

2

Select:

Select

Select[# != "" &] /@ test


>, <

DeleteMissing:

DeleteMissing

DeleteMissing[test /. "" -> Missing, 2]


"B" -> 6,   "C" -> 7

AssociationMap:

AssociationMap

AssociationMap[If[#[[2]] == "", Nothing, #] &] /@ test


<

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