yhat ggplot facet_wrap類型的錯誤

Question

我有我通過txt文件讀入數據幀大熊貓：

training = pd.read_csv('training_data.txt')

這些都是列：

>> print training.columns.values
['segment' 'cookie_id' 'num_visits' 'num_page_views']

我對分段顯示'num_page_views'的密度感興趣，如下所示：

plot = ggplot(training, aes(x='num_visits')) + geom_density() 
     + xlim(0,20) + facet_wrap(~ 'segment') 
print plot 

而且它提供了以下錯誤：

TypeError Traceback (most recent call last) in() 1 ----> 2 plot = ggplot(training, aes(x='num_visits')) + geom_density() +xlim(0,20) +facet_wrap(~ 'segment') 3 print plot

TypeError: bad operand type for unary ~: 'str'

Answer 1

在yhat ggplot，小面選項不採取 「〜」。你可以找到這是在documentation（複製在這裏爲了方便）：

import pandas as pd 

meat_lng = pd.melt(meat, id_vars=['date']) 

p = ggplot(aes(x='date', y='value'), data=meat_lng) 
p + geom_point() + \ 
    stat_smooth(colour="red") + \ 
    facet_wrap("variable") 

p + geom_hist() + facet_wrap("color") 

p = ggplot(diamonds, aes(x='price')) 
p + geom_density() + \ 
    facet_grid("cut", "clarity") 

p = ggplot(diamonds, aes(x='carat', y='price')) 
p + geom_point(alpha=0.25) + \ 
    facet_grid("cut", "clarity")