python how to conditionally create new column in pandas dataframe code example

Example 1: make a condition statement on column pandas

df['color'] = ['red' if x == 'Z' else 'green' for x in df['Set']]

Example 2: pandas create new column conditional on other columns

# For creating new column with multiple conditions
conditions = [
    (df['Base Column 1'] == 'A') & (df['Base Column 2'] == 'B'),
    (df['Base Column 3'] == 'C')]
choices = ['Conditional Value 1', 'Conditional Value 2']
df['New Column'] = np.select(conditions, choices, default='Conditional Value 1')