在一个图中创建多条线的 3D 图

Question

I'm currently having a small problem with plotting several different lines in a 3d plot. I have a list of lists containing three numpy arrays corresponding to the xyz coordinates for the three points on each line, ie

lines=[[array([10,0,0]),array([10,0,101.5]),array([-5,0,250])],[array([9,0,0]), array([9,0,101.5]),array([-4,0,250])]]

would represent 2 lines with 3 sets of xyz coordinates in each (the first one here would be (10,0,0),(10,0,101.5) and (-5,0,250)).

In general I would have n lines in this list each with 3 sets of xyz coordinates each. I would like to plot these lines on a single 3d plot with matplotlib. All I've managed to do so far is to create n plots each containing a single line.

Thanks for the help!

EDIT: I have a list 'lines' containing 'line' objects which are just lists themselves containing 3 numpy arrays for the 3 points on each line. I tried to use the following method:

for line in lines:
    fig = plt.figure()
    ax = fig.gca(projection='3d')

    z = []
    for i in [0,1,2]:
        z.append(line[i][2])

    x = []
    for i in [0,1,2]:
        x.append(line[i][0])

    y = []
    for i in [0,1,2]:
        y.append(line[i][1])

    ax.plot(x, y, z, label='path')

    plt.show()

I think I understand why this gives me 2 plots of lines 1 and 2 but I can't figure out a way to put both lines on the same plot.

Answer 1

You almost got it. The solution to your problem is simple, just move required statments out of for loop:

import matplotlib.pyplot as plt

lines=[[array([10,0,0]),array([10,0,101.5]),array([-5,0,250])],[array([9,0,0]), array([9,0,101.5]),array([-4,0,250])]]


fig = plt.figure()
ax = fig.gca(projection='3d')
for line in lines:

    z = []
    for i in [0,1,2]:
        z.append(line[i][2])

    x = []
    for i in [0,1,2]:
        x.append(line[i][0])

    y = []
    for i in [0,1,2]:
        y.append(line[i][1])

    ax.plot(x, y, z, label='path')

plt.show()

Answer 2

I had a similar problem trying to plot a 3D path between locations, and this was about the closest / most helpful solution I found. So just if anybody else is trying to do this and might find this similar solution sheds a bit of light :

for location in list_of_locations:
    x_list.append(locdata[location].x) # locdata is a dictionary with the co-ordinates of each named location
    y_list.append(locdata[location].y)
    z_list.append(locdata[location].z)

fig = plt.figure()
ax = fig.gca(projection='3d')
for i in range(len(x_list)-1):
    xs = [x_list[i], x_list[i+1]]
    ys = [y_list[i], y_list[i+1]]
    zs = [z_list[i], z_list[i+1]]
    ax.plot(xs,ys,zs)
plt.show()

I'm sure it doesn't need to be two separate for loops but for my little data set this was totally fine, and easy to read.