get number of elements that are not nan in pandas columns code example

Example 1: find position of nan pandas

# position of NaN values in terms of index
df.loc[pandas.isna(df["b"]), :].index

# position of NaN values in terms of rows that cotnain NaN
df.loc[pandas.isna(df["b"]), :]

Example 2: show all rows with nan for a column value pandas

df[df['col'].isnull()]