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

0 vote300 views1 answer
In pandas series hot to count the numer of appearences
Python
2 votes289 views1 answer
Comment concatener deux listes python
Python
0 vote311 views2 answers
3d graph python
Python
83 votes290 views6 answers
Python read csv
Python
0 vote299 views1 answer
Queue using linked list in python
Python
1 vote294 views1 answer
Make a message appear after specified Time python
Python
-1 vote278 views1 answer
What is text wrap in python
Python
0 vote291 views1 answer
How to bacome michael reeves in python
Python
0 vote295 views2 answers
Messagebox python pyqt
Python
0 vote309 views1 answer
How to get only one column from dataset in python
Python