Pandas update with condition

import pandas as pd
import numpy as np

df = pd.DataFrame({'value':np.arange(1000000)})

# Solution 1 - Fastest :
df['value'] = np.where(df['value'] > 20000, 0, df['value'])

# Solution 2:
df.loc[df['value'] > 20000, 'value'] = 0

# Solution 3:
df['value'] = df['value'].mask(df['value'] > 20000, 0)

# Solution 4 - Slowest, note that df.where applies where condition is wrong:
df['a'] = df.where(df.a <= 20000, 0)

Pandas filter and change value

df.loc[df['dollars_spent'] > 0, 'purchase'] = 1

Similar codes

2 votes130 views3 answers
How to increase bar width in python matplogtlib
Python
0 vote113 views1 answer
Extract n grams from text python
Python
10 votes131 views1 answer
Https://docs.djangoproject.com/en/2.0/howto/static-files/
Python
46 votes126 views6 answers
Comment in python
Python
0 vote121 views1 answer
If keyboard.is_pressed
Python
0 vote134 views2 answers
Python normalized correlation
Python
0 vote132 views1 answer
Ler arquivo xls no pandas
Python
0 vote86 views2 answers
Nested renamer is not supported pandas
Python
5 votes139 views6 answers
Valid Palindrome
Python
9 votes154 views5 answers
Get dummies pandas
Python