将列值与数据框中的另一个值进行比较（天气数据预报）

Question

我需要将我的列值（113 839 个值）与类别（位置）的平均值（降雨量）（44 个值）进行比较。如果它高于我的平均值，则应将其替换为平均值。我的 foreach 不起作用：

df_rainfall = pd.DataFrame(weather_train_data_total.groupby(['Location'])['Rainfall'].mean())

for column in weather_train_data_total[['Location']]:
result = weather_train_data_total[column]
print(result)
if result.equals(df_rainfall['Location']):
    result = df_rainfall['Rainfall']

Answer 1

没有数据，帮助总是很棘手，但你可以尝试适应这个：

# calculate and assign the average value for each group
df["mean_val"] = df.groupby("Location")["Rainfall"].transform("mean")

# identify rows in which the value is above the average
relevant_rows = df["mean_val"] < df["Rainfall"]

# replace these values with their corresponding average
df.loc[relevant_rows, ["Rainfall"]] = df.loc[relevant_rows, ["mean_val"]]["mean_val"]
df