Python library matplolib does a pretty good job.
ax.scatter instead of plt.scatter (as for 2d plots with import matplotlib.pyplot as plt)from mpl_toolkits.mplot3d import Axes3D
fig = plt.figure()
ax = Axes3D(fig)
ax.scatter(X, Y, Z, s = 10, linewidth = 1 )
ax.text(X, Y, Z, str(99))
ax.set_aspect('equal') (even though we should be able to).
This feature is not implemented yet (what?), so we add the following snippet to make it happen:extents = np.array([getattr(ax, 'get_{}lim'.format(dim))() for dim in 'xyz'])
sz = extents[:,1] - extents[:,0]
centers = np.mean(extents, axis=1)
maxsize = max(abs(sz))
r = maxsize/2
for ctr, dim in zip(centers, 'xyz'):
getattr(ax, 'set_{}lim'.format(dim))(ctr - r, ctr + r)
ax.set_box_aspect((1, 1, 1))
Alternatively, set x, y, and z ranges manually so that the length of the ranges are the same and do ax.set_box_aspect((1, 1, 1)):
XYZlim = [-3e-3, 3e-3]
ax.set_xlim3d(XYZlim+1e-3)
ax.set_ylim3d(XYZlim - 0.2e-3)
ax.set_zlim3d(XYZlim + 3e-3)
ax.set_aspect('equal')
ax.set_box_aspect((1, 1, 1))
Source
This snippet applies to ax, so we can convert it into a function def fix_aspect(ax): and call it.
plt.axis('scaled')
and specify the axes limits using
plt.xlim(a, b)
plt.ylim(c, d)
Caution: plt.axis('scaled') goes before setting plt.xlim() and plt.ylim() for the boundaries to remain faithful.
Plotting each line using a for loop is too slow. Use LineCollection and Line3DCollection instead.
The format of the data has to be in the following format:
[
[ [start_x_1, start_y_1, start_z_1], [end_x_1, end_y_1, end_z_1] ],
[ [start_x_2, start_y_2, start_z_2], [end_x_2, end_y_2, end_z_2] ],
[ [start_x_3, start_y_3, start_z_3], [end_x_3, end_y_3, end_z_3] ],
...
[ [start_x_N, start_y_N, start_z_N], [end_x_N, end_y_N, end_z_N] ]
]
where there are N lines that start with start and ends at end.
Note that The array has rank 3.
Example of such construction:
Given two (N,3) arrays P_start and P_end, to draw N lines between P_start[i] and P_end[i] in 3D, construct
ls = [ [p_start, p_end] for p_start, p_end in zip(P_start, P_end) ]
import matplotlib.pyplot as plt
from matplotlib.collections import Line3DCollection
lc = LineCollection3D(ls, linewidths=0.5, colors='b')
ax = plt.gca()
ax.add_collection(lc)
plt.show()
** Caution: ** For 2D plotting with LineCollection, you must add a scaling command like
ax.autoscale()
for the plots to show. Otherwise, no line will be printed. (weird bug?)
Note: that the collection added to ax (and not to plt).