dropna function in python code example

Example 1: dropping nan in pandas dataframe

df.dropna(subset=['name', 'born'])

Example 2: drop na pandas

>>> df.dropna(subset=['name', 'born'])
       name        toy       born
1    Batman  Batmobile 1940-04-25

Example 3: dropna pandas

>>> df.dropna(axis='columns')
       name
0    Alfred
1    Batman
2  Catwoman

Example 4: dropna threshold

#dropping columns having more than 50% missing values(1994/2==1000)
df=df.dropna(thresh=1000,axis=1)

Example 5: dropna pandas

df = pd.DataFrame({"name": ['Alfred', 'Batman', 'Catwoman'],
                   "toy": [np.nan, 'Batmobile', 'Bullwhip'],
                   "born": [pd.NaT, pd.Timestamp("1940-04-25"),
                            pd.NaT]})
df
# o/p
#        name        toy       born
# 0    Alfred        NaN        NaT
# 1    Batman  Batmobile 1940-04-25
# 2  Catwoman   Bullwhip        NaT


# Drop the rows where at least one element is missing.
df.dropna()
# o/p
#      name        toy       born
# 1  Batman  Batmobile 1940-04-25

# ref. https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.DataFrame.dropna.html

Example 6: dropna pandas

>>> df.dropna(subset=['name', 'toy'])
       name        toy       born
1    Batman  Batmobile 1940-04-25
2  Catwoman   Bullwhip        NaT