I want to draw x=0 and y=0 axis in my contour plot, using a white color. If that is too cumbersome, I would like to have a white dot denoting where the origin is.

My contour plot looks as follows and the code to create it is given below.

xvec = linspace(-5.,5.,100)                               
X,Y = meshgrid(xvec, xvec)                                
fig = plt.figure(figsize=(6, 4))                      
contourf(X, Y, W,100)                             

enter image description here

There are a number of options (E.g. centered spines), but in your case, it’s probably simplest to just use axhline and axvline.


import numpy as np
import matplotlib.pyplot as plt

xvec = np.linspace(-5.,5.,100)                               
x,y = np.meshgrid(xvec, xvec)
z = -np.hypot(x, y)                                

plt.contourf(x, y, z, 100)                             

plt.axhline(0, color="white")
plt.axvline(0, color="white")


enter image description here

Can’t you just overlay a straight line?