python pandas 計算結果をcsvの列に追記

pythonのpandasを使用してcsvデータを使用して計算を行い、計算結果をcsvに追記したいです。

python
1import pandas as pd
2
3df = pd.read_csv("list.csv")
4df2 = pd.read_csv("needtime.csv")
5new_file = "list_needtime.csv"
6results = df.merge(df2,on="id")
7results.to_csv(new_file,index=False)
8

上記のスクリプトで作成されたlist_needtime.csvが以下のファイルである時に、
新たな列『cost』を作成し、その中身に『0.33－total_time』の値を出力したいときに上記ファイルにどのように追記したらよろしいでしょうか。

ご教授いただけたら幸いです。

『list_needtime.csv』
id,x,y,total_time
60926,-8941.969874,-45122.21313,0.337304266
60926,-8941.969874,-45122.21313,0.224718083
60926,-8941.969874,-45122.21313,0.201283552
85222,-10719.76729,-43470.4291,0.156064931
85222,-10719.76729,-43470.4291,0.349723335
85222,-10719.76729,-43470.4291,0.285900337
81237,-8664.024773,-43629.69053,0.277924187
81237,-8664.024773,-43629.69053,0.164674301
81237,-8664.024773,-43629.69053,0.236382599
84105,-10236.66981,-44028.98672,0.1785224
84105,-10236.66981,-44028.98672,0.303805644
84105,-10236.66981,-44028.98672,0.208230811
97802,-9698.940734,-44312.66597,0.23124196
97802,-9698.940734,-44312.66597,0.246312806
97802,-9698.940734,-44312.66597,0.144448075
95831,-9110.267303,-44225.65537,0.259271853
95831,-9110.267303,-44225.65537,0.202606374
95831,-9110.267303,-44225.65537,0.181861712
88022,-8466.556894,-44451.5326,0.345955224
88022,-8466.556894,-44451.5326,0.162791666
88022,-8466.556894,-44451.5326,0.23344427
64734,-8596.208675,-45055.87246,0.348783661
64734,-8596.208675,-45055.87246,0.215640611
64734,-8596.208675,-45055.87246,0.212762948
55897,-10958.73994,-43566.02037,0.176328019
55897,-10958.73994,-43566.02037,0.367629679
55897,-10958.73994,-43566.02037,0.294575513

行動規範の内容に同意します

回答1件

import pandas as pd

df = pd.read_csv("list.csv")
df2 = pd.read_csv("needtime.csv")
new_file = "list_needtime.csv"
results = df.merge(df2,on="id")
results.to_csv(new_file,index=False)

df3 = pd.read_csv("list_needtime.csv")
df3["cost"] = (0.33) - df3["total_time"]
df3.to_csv(new_file,index=False)

これで求めることができたのですが、これで間違いないでしょうか？

投稿2019/11/13 09:32

huuuuuuu

総合スコア8