Matplotlib：在一行上显示多个标签

Posted 2023-02-16

【中文标题】Matplotlib：在一行上显示多个标签

【英文标题】：Matplotlib : display several labels on a single line

【发布时间】：2021-07-03 06:08:33

【问题描述】：

我有一个 DF，就像这个：

DF=pd.DataFrame.from_dict("date":["2019-01-01","2019-01-02","2019-01-03","2019-01-04","2019-01-05","2019-01-06","2019-01-07","2019-01-08","2019-01-09","2019-01-10"],
                           "temperature":[9,7,5,14,17,18,16,13.5,19,21],
                           "shorter_opinion":["bad & very bad","bad & very bad","bad & very bad","not good not bad","good & very good", "good & very good", "good & very good","not good not bad","not good not bad","bad & very bad"])

为了用一种颜色为每个 DF["shorter_opinion"] 值可视化，我创建了一个字典，并显示如下：

colors="good & very good":"green","not good not bad":"yellow","bad & very bad":"red"

plt.figure()
plt.scatter(x = DF["date"], y = DF["temperature"], c=DF["shorter_opinion"].map(colors))
plt.xticks(DF["date"][::3])
plt.legend(loc="upper right")
plt.show()

我尝试使用 Serie.Unique() 在图例中显示此单打状态

plt.figure()
plt.scatter(x = DF["date"], y = DF["temperature"], c=DF["shorter_opinion"].map(colors), label=DF["shorter_opinion"].unique())
plt.xticks(DF["date"][::3])
plt.legend(loc="upper right")
plt.show()

但是得到了这张照片

如何修改此代码以使每个值都位于正确的颜色旁边？

【参考方案1】：

一种解决方案可能是使用补丁，如下所示：

plt.figure()
plt.scatter(x = DF["date"], y = DF["temperature"], c=DF["shorter_opinion"].map(colors), label=DF["shorter_opinion"].unique())
plt.xticks(DF["date"][::3])
patches = [ plt.plot([],[], marker="o", ms=10, ls="", mec=None, color=colors[i], 
            label=i)[0]  for i in colors.keys() ]
plt.legend(colors.keys())
plt.show()