condition in dataframe pandas code example

Example 1: or condition in pandas

df1 = df[(df.a != -1) & (df.b != -1)]

Example 2: make a condition statement on column pandas

df.loc[df['column name'] condition, 'new column name'] = 'value if condition is met'

Example 3: if condition dataframe python

df.loc[df['age1'] - df['age2'] > 0, 'diff'] = df['age1'] - df['age2']