Merge pull request #183 from moorepants/plot-traj-with-no-inputs

Handle no input trajectories.

examples-gallery/plot_betts2003.py

@@ -119,6 +119,7 @@ def obj_grad(free):
 
 plt.tight_layout()
 
+# %%
 fig_y2, axes_y2 = plt.subplots(3, 1)
 
 axes_y2[0].plot(time, y2_m, '.k',
@@ -135,4 +136,10 @@ def obj_grad(free):
 
 plt.tight_layout()
 
+# %%
+prob.plot_constraint_violations(solution)
+
+# %%
+prob.plot_trajectories(solution)
+
 plt.show()

opty/direct_collocation.py

@@ -391,7 +391,15 @@ def plot_trajectories(self, vector, axes=None):
                     self.collocator.num_input_trajectories)
         traj_syms = (self.collocator.state_symbols +
                      self.collocator.input_trajectories)
-        trajectories = np.vstack((state_traj, input_traj))
+
+        trajectories = state_traj
+
+        if self.collocator.num_known_input_trajectories > 0:
+            known_traj = list(self.collocator.known_trajectory_map.values())
+            trajectories = np.vstack((trajectories, known_traj))
+
+        if self.collocator.num_unknown_input_trajectories > 0:
+            trajectories = np.vstack((trajectories, input_traj))
 
         if axes is None:
             fig, axes = plt.subplots(num_axes, 1, sharex=True,