Python: How to replace a column value with a new value without knowing its existing value?-CodePudding

I have a csv file with the below data.

Now, I want to replace any column value for all the rows with my required data without knowing the existing data present in the column.

Let's say, I want to replace all the values for "ofc Code" with "989".

I have tried below code:

import pandas as pd
import sys
csvFilePath=sys.argv[1]
columnName=sys.argv[2]
existingValue=int(sys.argv[3])
valueToBeUpdated=sys.argv[3]
df = pd.read_csv(csvFilePath)
df[columnName] = df[columnName].astype(object).replace({existingValue: valueToBeUpdated})
df.to_csv(csvFilePath, index=False)

Here the problem is I am accepting existing value of the column to replace it with new value. But the values in the column are dynamic. So I don't want to get that as input but replace all the values of the column with new value.

Pls help.

CodePudding user response：

Create dictionary for columns names with replacement values and pass to DataFrame.assign:

d = {columnName : valueToBeUpdated}

df = df.assign(**d)

If only one column name:

df[columnName] = valueToBeUpdated