如何用 Sympy 绘制点？

Question

我需要计算并绘制一个函数，它是前两个导数。然后，我需要在图形上绘制原始函数的最小值和最大值点。我已经计算了这些，但不知道如何绘制数据。最小/最大点的 x 值是 criticalPoints[]y 值是criticalPointsY[]这是出现错误的代码段。equation=CreateFunction();    firstDeriv=equation.diff(x);    secondDeriv=firstDeriv.diff(x);    print(equation);criticalPoints=solveset(firstDeriv,x);criticalPointsY=[];for a in criticalPoints:    criticalPointsY.append(equation.subs(x,a));p=plot(equation,firstDeriv,secondDeriv,(x,-10,10));# Need to add the critical points to the graph. We have them, and the# y values, but need to put them on the graphs.print(criticalPoints)print(criticalPointsY);for a in range(0, len(criticalPoints)):    xval=criticalPoints[a];    yval=criticalPointsY[a];    plt.plot(xval, yval, 'ro')p.show();plt.show();当我运行程序时，出现此错误。`Traceback (most recent call last):  File "--------", line 58, in <module>    xval=criticalPoints[a];TypeError: 'FiniteSet' object does not support indexing我尝试在 p 上绘制点并得到不同的错误    p.plot(criticalPoints,criticalPointsY);AttributeError: 'Plot' object has no attribute 'plot'有没有办法在这个图上绘制点？(p)