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@hamaguchi-amago
Created December 5, 2022 11:45
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import pandas as pd
# 都道府県名をindexとして読み込む
# [m]単位の人口を追加する
df = pd.read_csv("data.csv", index_col=0)
series_pop_million = df["population"].map(lambda x: x / 100)
series_pop_million.name = "population[m]"
df = pd.concat([df, series_pop_million], axis=1)
# 北海道
print(df.loc["北海道", :])
print()
# 北海道の面積
print(df.loc["北海道", "area"])
print()
# 北海道の面積 (データ型の違い)
print(df.loc["北海道", ["area"]])
print()
# 北海道の面積と人口 (複数取得)
print(df.loc["北海道", ["area", "population"]])
print()
# 条件指定
print(df.loc[df["area"] > 15000])
print()
@hamaguchi-amago
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ブログで作成しました。

【Python】pandasのデータフレームに loc 経由でアクセスする方法
https://neko-py.com/pandas-loc

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