mplot3d gives blank graph but no error

Question

So I am trying to plot a 3d chart using mplot3d with matplotlib. Code as following:

# generate the graph
# vols is a 2D array indexed by [maturity, strike].
def DrawGraph(self, strikes, maturities, vols):       
    import matplotlib.dates as dates
    import matplotlib.pyplot as pyplot

    # prepare data
    Y = dates.date2num(maturities)
    X, Y = numpy.meshgrid(strikes, Y)

    # plot
    fig = pyplot.figure()
    ax = fig.add_subplot(111, projection='3d')
    ax.plot_wireframe(X, Y, vols)
    pyplot.show()

Where maturities and strikes are 1D arrays, and vols is a 2D array with proper size. Everything runs proper and all data are valid. However, I got a totally blank window with nothing but gray background.

Anyone can give me some hints of what's going on? I suspect the version of matplotlib isn't right but not sure how to check it.

Thanks in advance.

Answer 1

In the version of matplotlib I have (1.2.1) the projection="3d" will raise an error unless you also include:

from mpl_toolkits.mplot3d import Axes3D

The only thing I can't check is the line

Y = dates.date2num(maturities)

As I am unfamiliar with what data type date2num expects, do you have any sample data?

Other than this everything works fine for me

Answer 2

What about

matplotlib.pyplot.ioff()

That solved my "nothing but gray background"-problem with mplot3d.