python - pandas 按条件分组制图

Question

如何以姓名为横坐标，分数为纵坐标，画 条形图？

Answer 1

试试

df.pivot('name', 'subject', 'score').plot.bar()

基本pandas 可视化原则是，使用pivot 或melt搞出制图需要的表格格式。

下列是我跑的代码(Jupyter Notebook)

% matplotlib inline
data = [ {"name":"abc", "subject":"A", "score":40}, {"name":"abc", "subject":"B", "score":60}, {"name":"abc", "subject":"C", "score":40},
        {"name":"xyz", "subject":"A", "score":10}, {"name":"xyz", "subject":"B", "score":90}, {"name":"xyz", "subject":"C", "score":30}]
df = pd.DataFrame(data)
df.pivot('name', 'subject', 'score').plot.bar()

结果：