How to check NaN in Pandas Dataframe null ๊ฐ ํ์ธ df.isnull() isnull(df) null ์๋ ๊ฐ ํ์ธ df.notnull() notnull(df) 1. ์์ dataframe ์์ฑ import pandas as pd import numpy as np dates = pd.date_range("20130101", periods=6) df = pd.DataFrame(np.random.randn(6, 4), index=dates, columns=list("ABCD")) 2. null ๊ฐ ์ถ๊ฐํ๊ธฐ 'NaN' ํน์ None์ ํตํด null๊ฐ์ ์์๋ก ์ถ๊ฐํ ์ ์๋ค. df['A'][1] = 'NaN' df['B'][2] = None df['C'][2] = 'NaN' d..