将一个 dataframe 中的一列与另一个单个值进行比较

Question

I have two dataframes:

data = {'a':['a','b','c','d','e','f','g'],
    'b':['Y','N','Y','Y','Y','N','Y']}
df = pd.DataFrame(data)

data1 = ['N']
df1 = pd.DataFrame(data1, columns=['Y/N'])

I would like to compare all elements in df with the single element in df2, so that the resulting dataframe is：

    a   b
0   b   N
1   f   N

How could I make it happen?

Answer 1

Since you only have one value on your second dataframe you can do this like so:

df[df["b"] == df1["Y/N"].iloc[0]]

Also you don't need a dataframe with only one string if all you want to do is get the rows with values "N" , you can do this by simply:

df[df["b"] == "N"]