python/test/trajpoly3.py

   1 #!/usr/bin/env python
   2 import os, sys
   3
   4 sys.path.insert(0, os.getcwd())
   5 prefix = os.path.join(sys.path[0], "build")
   6 if not os.path.exists(prefix):
   7     os.mkdir(prefix)
   8 try:
   9     import liba as a
  10     import numpy as np
  11     import matplotlib.pyplot as plt
  12 except Exception as e:
  13     print(e)
  14     exit()
  15
  16 t = (0, 1)
  17 p = (0, 1)
  18 v = (0, 1)
  19 data = np.arange(t[0], t[1], 0.01)
  20 traj = a.trajpoly3(t[1] - t[0], p[0], p[1], v[0], v[1])
  21 text_p = "p="
  22 if traj.p[0]:
  23     text_p += "%g" % (traj.p[0])
  24 if traj.p[1]:
  25     text_p += "%+g%s" % (traj.p[1], "t")
  26 if traj.p[2]:
  27     text_p += "%+g%s" % (traj.p[2], "t^2")
  28 if traj.p[3]:
  29     text_p += "%+g%s" % (traj.p[3], "t^3")
  30 text_p = text_p.replace("=+", "=")
  31 text_v = "v="
  32 if traj.v[0]:
  33     text_v += "%g" % (traj.v[0])
  34 if traj.v[1]:
  35     text_v += "%+g%s" % (traj.v[1], "t")
  36 if traj.v[2]:
  37     text_v += "%+g%s" % (traj.v[2], "t^2")
  38 text_v = text_v.replace("=+", "=")
  39 text_a = "a="
  40 if traj.a[0]:
  41     text_a += "%g" % (traj.a[0])
  42 if traj.a[1]:
  43     text_a += "%+g%s" % (traj.a[1], "t")
  44 text_a = text_a.replace("=+", "=")
  45 plt.figure("3 polynomial trajectory")
  46
  47 plt.subplot(311)
  48 plt.title("cubic polynomial trajectory")
  49 plt.ylabel("Position")
  50 plt.plot(data, traj.pos(data), "r-", label=text_p)
  51 plt.legend()
  52
  53 plt.subplot(312)
  54 plt.ylabel("Velocity")
  55 plt.plot(data, traj.vel(data), "b-", label=text_v)
  56 plt.legend()
  57
  58 plt.subplot(313)
  59 plt.ylabel("Acceleration")
  60 plt.plot(data, traj.acc(data), "g-", label=text_a)
  61 plt.legend()
  62
  63 plt.xlabel("t")
  64 plt.savefig(os.path.join(prefix, "trajectory_polynomial_3.png"))