[人工智能]pandas学习笔记：某一列字符类型转换为离散的数值标签；将某一列数值类型转换成独热码

import pandas as pd

将字符串变成离散的数值

• 整个“性别”列只有男和女

df = pd.DataFrame({"性别":["男","女","女","女","男","男","男","男","男","女","女","男"]})
df

• 将性别转换成可以用作数据分析的特征，把性别用离散值来表示

df["性别"] = pd.Categorical(df["性别"]).codes

df

将离散的数值变量变成独热码

from keras.utils import to_categorical

y = to_categorical(df["性别"],num_classes=2)

y

array([[0., 1.],
       [1., 0.],
       [1., 0.],
       [1., 0.],
       [0., 1.],
       [0., 1.],
       [0., 1.],
       [0., 1.],
       [0., 1.],
       [1., 0.],
       [1., 0.],
       [0., 1.]], dtype=float32)

pd.concat([df,pd.DataFrame(y)],axis=1)