使用matplotlib从CSV数据绘制3D轨迹

Question

I'm trying to plot a 3D trajectory of a vehicle that comes from a CSV file, plotting is easy, I want to make the animation, actually a "replay" of the movements. I based my code from this example ( http://matplotlib.org/examples/animation/simple_3danim.html ) and then just modify it to only plot one line and to read the data from a CSV file being read by pandas, the code looks like this:

import numpy as np
import matplotlib.pyplot as plt
import mpl_toolkits.mplot3d.axes3d as p3
import matplotlib.animation as animation
import pandas as pd

def update_lines(num, data, line):
    # NOTE: there is no .set_data() for 3 dim data...
    x = data['x'].values[num]
    y = data['y'].values[num]
    z = data['z'].values[num]
    line[0].set_data(x,y)
    line[0].set_3d_properties(z)
    print z
    return line

# Attaching 3D axis to the figure
fig = plt.figure()
ax = p3.Axes3D(fig)

# Reading the data from a CSV file using pandas
data = pd.read_csv('data.csv',sep=',',header=0)

# Creating fifty line objects.
# NOTE: Can't pass empty arrays into 3d version of plot()
x = np.array([0])
y = np.array([0])
z = np.array([0])

line = ax.plot(x, y, z)

# Setting the axes properties
ax.set_xlim3d([0.0, 3.0])
ax.set_xlabel('X')

ax.set_ylim3d([0.0, 3.0])
ax.set_ylabel('Y')

ax.set_zlim3d([0.0, 2.0])
ax.set_zlabel('Z')

ax.set_title('3D Test')

# Creating the Animation object
line_ani = animation.FuncAnimation(fig, update_lines, len(data), fargs=(data, line),
                                   interval=10, blit=False)

plt.show()

I print the z just to see if the data is being iterated correctly, but all I get is a white plot like this:

Plot showing absolutely nothing.

Answer 1

at least, there are two issues with your code:

1. the way of how data is build
2. length of frames per second

here is the modified working example, please take a look how data variable was arranged:

import numpy as np
import matplotlib.pyplot as plt
import mpl_toolkits.mplot3d.axes3d as p3
import matplotlib.animation as animation
import pandas as pd
from sys import exit
def update_lines(num, data, line):
    # NOTE: there is no .set_data() for 3 dim data...
    line.set_data(data[0:2, :num])    
    line.set_3d_properties(data[2, :num])    
    return line

# Attaching 3D axis to the figure
fig = plt.figure()
ax = p3.Axes3D(fig)

# Reading the data from a CSV file using pandas
repo = pd.read_csv('data.csv',sep=',',header=0)
data = np.array((repo['x'].values, repo['y'].values, repo['z'].values))
print data.shape[1]
#exit()

# Creating fifty line objects.
# NOTE: Can't pass empty arrays into 3d version of plot()
line = ax.plot(data[0, 0:1], data[1, 0:1], data[2, 0:1])[0]

# Setting the axes properties
ax.set_xlim3d([-2.0, 2.0])
ax.set_xlabel('X')

ax.set_ylim3d([-2.0, 2.0])
ax.set_ylabel('Y')

ax.set_zlim3d([-2.0, 2.0])
ax.set_zlabel('Z')

ax.set_title('3D Test')

# Creating the Animation object
line_ani = animation.FuncAnimation(fig, update_lines, data.shape[1], fargs=(data, line), interval=50, blit=False)

plt.show()

you can watch the beauty of that flight just being tracked