有条件地从熊猫数据框中删除行

Question

I have a pandas data frame...in one of its columns, there is list of strings. I want to define a condition for it. This condition is that if a list in each row has the length less than 2 strings, drop whole row from data frame and make a new one. I use to write this code for it . but it doesn't work!

new_dataframe = dataframe.drop(x for x in dataframe['specific column'][:] if x in len(dataframe['specific column'][:])<2)

[:] is there to consider all rows of this specific column

and I receive this error:

'labels [<generator object <genexpr> at 0x7fcc19dd80a0>] not contained in axis'

Answer 1

Try:

# Test dataframe with lists of strings
df = pd.DataFrame({"specific column": [
    ["a", "b"],
    ["a", "b", "c",],
    ["a",],
    ["a", "b", "c", "d"]], })

# Select indices of rows with less than 2 items in list
ix = df["specific column"].str.len() < 2

# Select all other rows
df.loc[~ix]