Как решить недопустимое значение, встречающееся в double_scalars в Mayavi с помощью numpy

Question

Вот эта ошибкаscale_max - scale_min)

мой код указан ниже:

class Visualization(HasTraits):
    scene = Instance(MlabSceneModel, ())

    @on_trait_change('scene.activated')
    def update_plot(self):
        # x = np.linspace(0,10,50)
        # y = np.linspace(0,15,50)
        # z = np.linspace(0,8,50)

        mycsv = csv.reader(open("./Tunnel.saf.csv"))
        for row in mycsv:
           x = float(row[0])
           y = float(row[1])
           z = float(row[2])

        X, Y, Z = np.meshgrid(x, y, z)

        s = np.cos(X) + np.sin(Y) + Z**0.5
        b1 = np.percentile(s, 20)
        b2 = np.percentile(s, 80)

        s = pipeline.volume(pipeline.scalar_field(s), vmin=b1, vmax=b2)
            #s = surf(x, y, f, colormap="Oranges")
            #s = outline()
        s = axes()
                #s = orientation_axes()
        #cs = contour_surf(x, y, f, contour_z=0)

        #self.scene.mlab.mesh(r[0],r[1],r[2], scalars=Y_lm.real, colormap="cool")

    view = View(Item('scene', editor=SceneEditor(scene_class=MayaviScene),
                     height=250, width=300, show_label=False),
                resizable=True # We need this to resize with the parent widget
                )