Matplotlib 3D scatter plot with color gradient

Question

How can I create a 3D plot with a color gradient for the points? See the example below, which works for a 2D scatter plot.

Edit (thanks to Chris): What I\'m expectin

Answer 1

Following works: I can't figure out why yours doesn't. You should be able to set color as a sequence of RGBA floats, or just sequence of floats.

# Create Map
cm = plt.get_cmap("RdYlGn")

x = np.random.rand(30)
y = np.random.rand(30)
z = np.random.rand(30)
col = np.arange(30)

# 2D Plot
fig = plt.figure()
ax = fig.add_subplot(111)
ax.scatter(x, y, s=10, c=col, marker='o')  

# 3D Plot
fig = plt.figure()
ax3D = fig.add_subplot(111, projection='3d')
p3d = ax3D.scatter(x, y, z, s=30, c=col, marker='o')                                                                                

plt.show()

However, in help of scatter, I see the following, it may be related.

    A :class:`matplotlib.colors.Colormap` instance or registered
    name. If *None*, defaults to rc ``image.cmap``. *cmap* is
    only used if *c* is an array of floats.