A grid is interpolated with scipy's griddata() and contains values and NaNs. However, when the grid is plotted with mplot3d's plot_surface() there are gaps in the surface (see upper plot). The lower the view height, the more of such gaps are rendered. When the grid is plotted in 2D with imshow() there are no gaps (see lower plot).
Comparison plot_surface and imshow
Here is a close-up:
I couldn't find an answer to this problem and I am wondering whether this is a known issue.
This small example reproduces the problem: (data.txt)
import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
Z = np.loadtxt('data.txt')
X = np.linspace(0,3,301)
Y = np.linspace(0,3,301)
X = np.array([X,]*(301)).transpose()
Y = np.array([Y,]*(301))
fig = plt.figure(figsize=(15,15), dpi=100)
ax = fig.add_subplot(2, 1, 1, projection='3d')
plt.hold(True)
ax.view_init(40,300)
surf = ax.plot_surface(X, Y, Z, cmap='jet', rstride=1, cstride=1, antialiased=False, shade=False, alpha=1.0, linewidth=0, vmin=0.25, vmax=0.35);
ax.invert_yaxis()
ax.dist = 11
ax = fig.add_subplot(2, 1, 2)
plt.hold(True)
plt.imshow(Z, cmap='jet', vmin=0.25, vmax=0.35, origin='lower');
plt.show()