Numpy Beginner's Guide (Update)

Time for action – plotting in three dimensions

We will plot a simple three-dimensional function:

1. Use the 3D keyword to specify a three-dimensional projection for the plot:

   ax = fig.add_subplot(111, projection='3d')

2. To create a square two-dimensional grid, use the meshgrid() function to initialize the x and y values:

   u = np.linspace(-1, 1, 100)
   
   x, y = np.meshgrid(u, u)

3. We will specify the row strides, column strides, and the color map for the surface plot. The strides determine the size of the tiles in the surface. The choice for color map is a matter of taste:

   ax.plot_surface(x, y, z,  rstride=4, cstride=4, cmap=cm.YlGnBu_r)

   The result is the following ...