I have a starting balance of 'Points = 500', and as I run through this data frame, the point value will update as it goes through every row. Here is the data frame:

What I'm trying to do is update 'Points' based on the following conditions for every row:

For example, row 1:

If A_yes = 1 then multiply the current 'Points' value by the first row in the 'A' column (2.43). (Otherwise if it was B_yes that equalled 1, then the 'Points' value would have been multiplied by the first row in the 'B' column (1.55)).

So Points = 500 * 2.43 = 1215

Second row:

Now that Points = 1215, this will be used for the next row and the same process will be followed, If A_yes = 1 then multiply 'Points' by the value in the A column (2.58), however because A_yes = 0, then if B_yes = 1 then multiply 'Points' by the 'B' column (1.49) and updated 'Points' now = 1810.35

I'm new to pandas and not sure how to create a function that will run through all the rows and update the 'Points' value in this way

CodePudding user response：

You can multiple columns A,B by Yes columns, then multiple first row by 500, then sum both columns and add cumulative product by Series.cumprod:

cols = ['A','B']

df1 = df[['A','B']].mul(df[['A_yes','B_yes']].to_numpy())
df1.loc[0, cols] *= 500

df['Point'] = df1.sum(axis=1).cumprod()
print (df)
      A     B  A_yes  B_yes       Point
0  2.43  1.55      1      0  1215.00000
1  2.58  1.49      0      1  1810.35000
2  1.61  2.32      1      0  2914.66350
3  2.70  1.46      1      0  7869.59145