Python, How to populate dataframe column with values from another column which aren't in a list-CodePudding

I've got a dataframe column.A containing lists and I'm trying to populate a new column with a list of values in columnA that aren't present in a secondary list.

d = {'colA': [['UVB', 'NER', 'GGR'], ['KO'], ['ERK1', 'ERK2'], []]}
df = pd.DataFrame(data=d)

The code I've tried is:

finaldf['colB'] = [i for i in list(finaldf.AllGenes) if i not in List]

But this just populates colB with the same list of values thats in colA

CodePudding user response：

Not totally clear what you want

d = {'colA': [['UVB', 'NER', 'GGR'], ['KO'], ['ERK1', 'ERK2'], []]}
df = pd.DataFrame(data=d)
"""
              colA
0  [UVB, NER, GGR]
1             [KO]
2     [ERK1, ERK2]
3               []
"""
# filter
dont_include = ["NER", "ERK2"]
df["colB"] = df["colA"].apply(
    lambda col_a: [e for e in col_a if e not in dont_include]
)
"""
              colA        colB
0  [UVB, NER, GGR]  [UVB, GGR]
1             [KO]        [KO]
2     [ERK1, ERK2]      [ERK1]
3               []          []
"""

try using this.