使用 pandas 将 [左侧单元格中的值] 与 [左侧单元格上方的值总和] 的比率转换为新列

Ratio of [value in cell to the left] to [sum of values above cell to the left] into a new column using pandas

我在名为 ACTION_DATA 的数据框中有一个名为 Bets of poker bets 的列。我想用下注底池比率(底池百分比)

创建一个新列

下注底池比率等于下注列中同一行的下注除以下注中所有先前下注的总和 column.The 前两个下注应始终标记为“小盲注”和“大盲注”。

例如,对于每个 Bets 列,我想要一个 Bet-to-Pot Ratio 列来显示该比率,如下所示:

| Bets | Bet-To-Pot-Ratio | Formula 
| -------- | -------------- |-----|
| .02    |  Small Blind     | 
| .05   |  Big Blind        | 
|.15 | 214% | .15/(.02 + .05)


| Bets | Bet-To-Pot-Ratio |Formula 
| -------- | -------------- |---| 
| .02    |  Small Blind      | 
| .05   |  Big Blind         | 
| .17 | 243% | .17/(.02 + .05)

| Bets | Bet-To-Pot-Ratio | Formula
 | -------- | -------------- |---| 
| .02    |  Small Blind      | 
| .05   |  Big Blind         | 
| .05 | 71% | .05/(.02 + .05) | 
|.05| 42% | .05/(.02 + .05 + .05)|
|.05| 29% | .05/(.02 + .05 + .05 + .05)|
|.03| 14% |.03/(.02 + .05 + .05 + .05 + .05)|

| Bets | Bet-To-Pot-Ratio | Formula
| -------- | -------------- |---| 
| .02    |  Small Blind      | 
| .05   |  Big Blind         | 
| .1 |  .1/(.02 + .05) |
|.2| 118% | .2/(.02 + .05 + .1)|
|.99| 268% | .99/(.02 + .05 + .1 + .2)|
|2.87| 211% |2.87/(.02 + .05 + .1 + .2 + .99)|

我尝试了一些跨列计算,如下所示,但我认为我需要计算行数

import pandas as pd
df = [0, 0, 0]
df = pd.DataFrame(df).transpose()
df.columns = ['Bet Size', 'Pot', '% of Pot']

df['Pot'][0] = 0
df['% of Pot'][0] = 0

for _ in range(1, 10):
  df.loc[_, 'Bet Size'] = df.loc[_-1, 'Bet Size']+1
  df.loc[_, 'Pot'] = df.loc[_, 'Bet Size']+100
  df.loc[_, '% of Pot'] = df.loc[_-1, 'Pot']+df.loc[_, 'Pot'] + 1
df

您可以使用shift()cumsum()得到答案:

bets = [0.02, 0.05, 0.1, 0.2, 0.99, 2.87]
df = pd.DataFrame({ "bets" : bets})

df['ratio'] = df['bets']/(df['bets'].shift(1).cumsum())

print(df)

   bets     ratio
0  0.02       NaN
1  0.05  2.500000
2  0.10  1.428571
3  0.20  1.176471
4  0.99  2.675676
5  2.87  2.110294