Setting aspect ratio of 3D plot

Question

I am trying to plot a 3D image of the seafloor from the data of a sonar run over a 500m by 40m portion of the seafloor. I am using matplotlib/mplot3d with Axes3D and I want

Answer 1

The answer to this question works perfectly for me. And you do not need to set up any ratio, it does everything automatically.

Answer 2

That how i solved the wasted space problem:

try: 
    self.localPbAspect=self.pbaspect
    zoom_out = (self.localPbAspect[0]+self.localPbAspect[1]+self.localPbAspect[2]) 
except AttributeError: 
    self.localPbAspect=[1,1,1]
    zoom_out = 0 
xmin, xmax = self.get_xlim3d() /  self.localPbAspect[0]
ymin, ymax = self.get_ylim3d() /  self.localPbAspect[1]
zmin, zmax = self.get_zlim3d() /  self.localPbAspect[2]

# transform to uniform world coordinates 0-1.0,0-1.0,0-1.0
worldM = proj3d.world_transformation(xmin, xmax,
                                         ymin, ymax,
                                         zmin, zmax)

# look into the middle of the new coordinates
R = np.array([0.5*self.localPbAspect[0], 0.5*self.localPbAspect[1], 0.5*self.localPbAspect[2]])
xp = R[0] + np.cos(razim) * np.cos(relev) * (self.dist+zoom_out)
yp = R[1] + np.sin(razim) * np.cos(relev) * (self.dist+zoom_out)
zp = R[2] + np.sin(relev) * (self.dist+zoom_out)
E = np.array((xp, yp, zp))

Answer 3

An issue has been opened over at github: https://github.com/matplotlib/matplotlib/issues/8593

The above solutions don't seem to work any more. One has to edit the get_proj function inside site-packages\mpl_toolkits\mplot3d\axes3d.py in the following way now:

        try:
            self.localPbAspect = self.pbaspect
        except AttributeError:
            self.localPbAspect = [1,1,1]

        xmin, xmax = ( lim / self.localPbAspect[0] for lim in self.get_xlim3d() )
        ymin, ymax = ( lim / self.localPbAspect[1] for lim in self.get_ylim3d() )
        zmin, zmax = ( lim / self.localPbAspect[2] for lim in self.get_zlim3d() )

Answer 4

Add following code before savefig:

ax.auto_scale_xyz([0, 500], [0, 500], [0, 0.15])

If you want no square axis:

edit the get_proj function inside site-packages\mpl_toolkits\mplot3d\axes3d.py:

xmin, xmax = np.divide(self.get_xlim3d(), self.pbaspect[0])
ymin, ymax = np.divide(self.get_ylim3d(), self.pbaspect[1])
zmin, zmax = np.divide(self.get_zlim3d(), self.pbaspect[2])

then add one line to set pbaspect:

ax = fig.gca(projection = '3d')
ax.pbaspect = [2.0, 0.6, 0.25]