[FIXED] Iteration using pandas dataframe values

Issue

While turning around the iteration, if the conditions are satisfied then the value is changed. However, the original dataframe remains unchanged. Is there a way to solve this?

(I know itertuples, iterrows loc can available. But I want to use values. (more faster))

import panda as pd
df = pd.read_csv(filename)
for value in df.values:
  if A:
    value[2] = 3
  print(value) # changed
df.to_csv(newfilename) # unchanged

Solution

I soled using iat.

import panda as pd
df = pd.read_csv(filename)
cnt = 0
for value in df.values:
  if A:
    #value[2] = 3
    df[cnt, 2] = 3
  print(value) # changed
  cnt += 1
df.to_csv(newfilename) # changed

Additionally, iteration (sec) : df.values < itertuples < iterrows

Answered By - 최민수