python画弯曲的线_matplotlib：绘制类似pyplot.arrow的弯曲箭头？

这是我最后使用的；这是一个小技巧，只需在一个Arc的结尾画出笔直的arrow头：import numpy as np

import matplotlib.pyplot as plt

from matplotlib.patches import Arc

def circarrow(self,diameter,centX,centY,startangle,angle,**kwargs):

startarrow=kwargs.pop("startarrow",False)

endarrow=kwargs.pop("endarrow",False)

arc = Arc([centX,centY],diameter,diameter,angle=startangle,

theta1=np.rad2deg(kwargs.get("head_length",1.5*3*.001)) if startarrow else 0,theta2=angle-(np.rad2deg(kwargs.get("head_length",1.5*3*.001)) if endarrow else 0),linestyle="-",color=kwargs.get("color","black"))

self.axes().add_patch(arc)

if startarrow:

startX=diameter/2*np.cos(np.radians(startangle))

startY=diameter/2*np.sin(np.radians(startangle))

startDX=+.000001*diameter/2*np.sin(np.radians(startangle)+kwargs.get("head_length",1.5*3*.001))

startDY=-.000001*diameter/2*np.cos(np.radians(startangle)+kwargs.get("head_length",1.5*3*.001))

self.arrow(startX-startDX,startY-startDY,startDX,startDY,**kwargs)

if endarrow:

endX=diameter/2*np.cos(np.radians(startangle+angle))

endY=diameter/2*np.sin(np.radians(startangle+angle))

endDX=-.000001*diameter/2*np.sin(np.radians(startangle+angle)-kwargs.get("head_length",1.5*3*.001))

endDY=+.000001*diameter/2*np.cos(np.radians(startangle+angle)-kwargs.get("head_length",1.5*3*.001))

self.arrow(endX-endDX,endY-endDY,endDX,endDY,**kwargs)

import types

plt.circarrow = types.MethodType(circarrow,plt)

函数名为circarrow，作为参数，传递直径、圆心的两个坐标、弧开始的角度和弧应该传递的总角度，以及传递给pyplotarrow的任何参数。若要在弧的开头绘制箭头，请指定startarrow=True，而endarrow=True将在弧的结尾启用箭头。

下面是一个示例图像，您还可以看到箭头样式与直箭头一致：plt.plot(0,0,"o",markersize=10,color="black",mfc="none")

plt.circarrow(.85,0,0,0.05*120,.9*120,startarrow=True,width=0,head_width=.03,head_length=.045,length_includes_head=True,color="black")

plt.circarrow(.85,0,0,1.05*120,.9*120,startarrow=True,endarrow=True,width=0,head_width=.03,head_length=.045,length_includes_head=True,color="black")

plt.arrow(-.2,-.33,.6,+.33,width=0,head_width=.03,head_length=.045,length_includes_head=True,color="black")

plt.axes().set_xlim(-.5,.5)

plt.axes().set_ylim(-.5,.5)

plt.axes().set_aspect(1)

plt.show()