Matplotlib 没有在数据点之间绘制线

Question

我有一组从 csv 绘制的降雪累积数据，如下所示：

我正在尝试根据 RAP 数据绘制 GFS 数据，RAP 将完美地绘制连接它们的点和线。但是，GFS 只会绘制为点数据：，而我一生都没有找到一种方法来绘制 GFS 数据，并用一条线连接这些点。这是我一直在使用的代码：

gfs = df['GFS']
rap = df['RAP']
fig2, ax2 = plt.subplots(figsize=(10,8))
ax2.plot(fh,gfs,'ob-') 
ax2.plot(fh,rap,marker='x')
ax2.tick_params(which='major',labelsize='12')
ax2.grid(which='major', color='#CCCCCC', linestyle='-')
plt.xticks(rotation='90')
plt.xlabel('Forecast Run')
plt.ylabel('Snowfall Accumulation (in.)')
plt.legend()

任何帮助和指导将不胜感激！

使用 ~np.isnan(): 编辑图表

Answer 1

要扩展@ImportanceOfBeingErnest 的答案，您可以像这样删除缺失值：

替换

ax2.plot(fh,gfs,'ob-') 

与

ax2.plot(fh[~np.isnan(gfs)],gfs[~np.isnan(gfs)],'ob-') 

更新：

上述方法可能会导致改变 x 轴的顺序。这是一个解决方法：

import pandas as pd
import numpy as np
import matplotlib.pyplot as plt

# make up some fake data
df = pd.DataFrame({"GFS": [np.nan, np.nan, 1, 2, np.nan, 
                          2, 3, np.nan, np.nan, 4], 
                    "RAP": [-2.45832646,  0.56266567, -0.4453474 , 
                            -0.85447845, -1.34830127,
                            -0.38113925, -0.41400397,  
                            np.nan, -0.78764545, -0.02807674]})
fh = np.array(["Fri 4 am", "Fri 6 am","Fri 8 am","Fri 10 am",
                "Fri 6 pm","Fri 10 pm","Sat 4 am","Sat 6 am",
                "Sat 8 am","100az 10 am"
                ])
gfs = df['GFS']
rap = df['RAP']


fig2, ax2 = plt.subplots(figsize=(10,8))
# workaround to set the order of xlabels
ax2.plot(fh, [np.nan]*len(fh)) 
# remove nan's  so that the points are connected
ax2.plot(fh[~np.isnan(gfs)], gfs[~np.isnan(gfs)], "ob-") 
ax2.plot(fh[~np.isnan(rap)],rap[~np.isnan(rap)],marker='x')
ax2.tick_params(which='major',labelsize='12')
ax2.grid(which='major', color='#CCCCCC', linestyle='-')
plt.xticks(rotation='90')
plt.xlabel('Forecast Run')
plt.ylabel('Snowfall Accumulation (in.)')