apply

来源： https://stackoverflow.com/questions/48590488/map-str-contains-across-pandas-dataframe

来源： https://stackoverflow.com/questions/48590488/map-str-contains-across-pandas-dataframe

来源： https://stackoverflow.com/questions/25588426/pasting-elements-of-two-vectors-alphabetically

来源： https://stackoverflow.com/questions/47513408/pandas-dataframe-check-if-column-value-is-in-column-list

来源： https://stackoverflow.com/questions/47513408/pandas-dataframe-check-if-column-value-is-in-column-list

来源： https://stackoverflow.com/questions/47513408/pandas-dataframe-check-if-column-value-is-in-column-list

来源： https://stackoverflow.com/questions/47513408/pandas-dataframe-check-if-column-value-is-in-column-list

来源： https://stackoverflow.com/questions/63400773/pandas-1-1-0-apply-function-is-altering-the-row-in-place

问题 I have a huge dataframe df1, whose oversimplified version consists of 3 columns, "Words", "Frequency" and "Letters": Words Frequency Letters flower/tree 0.15 a(0.1) tree 0.67 a(0.4) planet 0.85 b(0.4) tree/planet 0.42 c(0.5) tree 0.89 a(0.6) flower 0.21 b(0.4) flower/planet 0.53 b planet 0.07 a Using R (dplyr, apply family functions, etc.) I would like to count the number of times every letter (a, b, c) of the "Letter" column is associated with every single word from the "Word" column (flower

问题 I have a huge dataframe df1, whose oversimplified version consists of 3 columns, "Words", "Frequency" and "Letters": Words Frequency Letters flower/tree 0.15 a(0.1) tree 0.67 a(0.4) planet 0.85 b(0.4) tree/planet 0.42 c(0.5) tree 0.89 a(0.6) flower 0.21 b(0.4) flower/planet 0.53 b planet 0.07 a Using R (dplyr, apply family functions, etc.) I would like to count the number of times every letter (a, b, c) of the "Letter" column is associated with every single word from the "Word" column (flower