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 vote226 views1 answer
Plt.hist using bins
Python
2 votes232 views1 answer
Predicate
Python
5 votes224 views1 answer
Python pyautogui how to change the screenshot location
Python
0 vote227 views1 answer
How to do a dark theam in pycgram
Python
6 votes217 views1 answer
Python drop axis
Python
1 vote249 views1 answer
Flask send client to another web page
Python
0 vote223 views2 answers
Register temporary table pyspark
Python
17 votes225 views6 answers
Data types
Python
0 vote214 views1 answer
Python get names of input arguments
Python
0 vote220 views1 answer
Python declare immutable variable
Python