如何使用一列的值来访问另一列的值
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所以如何获取价值＆＃39; bleh＆＃39;每一行？
import numpy
impot pandas
numpy.random.seed(123)
df = pandas.DataFrame((numpy.random.normal(0, 1, 10)), columns=[['Value']])
df['bleh'] = df.index.to_series().apply(lambda x: numpy.random.randint(0, x + 1, 1)[0])
感谢@ScottBoston。我的DF构造函数有一层df.Value.iloc[df['bleh']]
太多了。
正确答案是：
[]答案 0 :(得分：1)
尝试：
df['Value'].tolist()
输出：
[-1.0856306033005612,
0.9973454465835858,
0.28297849805199204,
-1.506294713918092,
-0.5786002519685364,
1.651436537097151,
-2.426679243393074,
-0.42891262885617726,
1.265936258705534,
-0.8667404022651017]
您的数据框构造函数仍需要修复。
您在寻找：
df.set_index('bleh')
输出：
Value
bleh
0 -1.085631
1 0.997345
2 0.282978
1 -1.506295
4 -0.578600
0 1.651437
0 -2.426679
4 -0.428913
1 1.265936
7 -0.866740
如果是这样，您的数据框构造函数中包含[]的额外集合。
np.random.seed(123)
df = pd.DataFrame((np.random.normal(0, 1, 10)), columns=['Value'])
df['bleh'] = df.index.to_series().apply(lambda x: np.random.randint(0, x + 1, 1)[0])
columns参数列表不是列表列表。