[Python] Pandas: within groupby groups, return max value if it is at least 3x greater than any...

I need to group a dataframe by the FeatureID column, and then test each group to determine if the max value in the group's gene_count column is at least 3 times greater than any of the other gene_count values in the group.

If no value is at least 3x times greater, I need to return the row with the max value in the feature_div column.

At this point, if there is not a row with max gene_count (aka they are all tied) and no row with max feature_div, then that FeatureID should not be returned.

So the pseudocode logic is:

For each group in df.groupby("FeatureID"):
If max(gene_count) 3x > all other gene_counts in group:
return this row
Elif:
there is a max(feature_div) return this row
Else:
max(gene_count) is not >3 x higher than all other gene_counts in group
and the feature_div scores are all tied
pass


Here is my dataframe:

FeatureID gene feature_div gene_count
1_1001_1028 NTRK1.1 2 2.0
1_1001_1028 TP53.1 1 2.0
1_1001_193 MTOR.1 1 9.0
1_1001_193 TP53.2 1 3.0
1_1003_1034 EGFR.1 3 4.0
1_1003_1034 EGFR.5 3 4.0
1_1008_823 ABL1.1 1 2.0
1_1008_823 BRCA2.2 2 2.0


My desired output would look like this:

FeatureID gene feature_div gene_count
1_1001_1028 NTRK1.1 2 2.0
1_1001_193 MTOR.1 1 9.0
1_1008_823 BRCA2.2 2 2.0


In the first row, NTRK1.1 gets selected because the counts are tied, but it has higher feature_div than TP53.1.

In the second row, MTOR.1 gets selected because the gene_count is 3x higher than TP53.3.

In the third row BRCA2.2 is selected because the gene_count are tied but it has higher feature_div.

1_1003_1034 is not returned because the gene_count is not 3 times higher than the other options, and there is no feature_div higher than the other options.

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