小编Mat*_*u22的帖子

我的老师说,在图表中我必须标记轴0, 0.25, 0.5而不是0.00,0.25,0.50,....我知道如何将它标记为0.00,0.25,0.50 (plt.yticks(np.arange(-1.5,1.5,.25))),但是,我不知道如何以不同的精度绘制ticklabels.

我试过这样做

plt.yticks(np.arange(-2,2,1))
plt.yticks(np.arange(-2.25,2.25,1))
plt.yticks(np.arange(-1.5,2.5,1))

无济于事.

假设我有一个像这样的Panda DataFrame

import pandas as pd


a=pd.Series([{'Country'='Italy','Name'='Augustina','Gender'='Female','Number'=1}])
b=pd.Series([{'Country'='Italy','Name'='Piero','Gender'='Male','Number'=2}])
c=pd.Series([{'Country'='Italy','Name'='Carla','Gender'='Female','Number'=3}])
d=pd.Series([{'Country'='Italy','Name'='Roma','Gender'='Female','Number'=4}])
e=pd.Series([{'Country'='Greece','Name'='Sophia','Gender'='Female','Number'=5}])
f=pd.Series([{'Country'='Greece','Name'='Zeus','Gender'='Male','Number'=6}])

df=pd.DataFrame([a,b,c,d,e,f])

然后,我用multiindex排序,就像

df.set_index(['Country','Gender'],inplace=True)

现在,我想知道如何计算来自意大利的人数,或者我在数据框中有多少希腊女性.

我试过了

df['Italy'].count()

和

 df['Greece']['Female'].count()

.它们都不起作用,

谢谢