Don't call pyplot.show when examples are being tested.

roryyorke · roryyorke · commit 96c31f419fca · 2019-01-02T07:51:02.000+02:00
diff --git a/examples/phaseplots.py b/examples/phaseplots.py
@@ -4,6 +4,8 @@
 # This file contains examples of phase portraits pulled from "Feedback
 # Systems" by Astrom and Murray (Princeton University Press, 2008).
 
+import os
+
 import numpy as np
 import matplotlib.pyplot as mpl
 from control.phaseplot import phase_plot
@@ -120,4 +122,5 @@ def saddle_ode(x, t):
 mpl.xlabel('$x_1$'); mpl.ylabel('$x_2$');
 mpl.title('Undamped system\nLyapunov stable, not asympt. stable')
 
-mpl.show()
+if 'PYCONTROL_TEST_EXAMPLES' not in os.environ():
+    mpl.show()
diff --git a/examples/robust_siso.py b/examples/robust_siso.py
@@ -4,6 +4,8 @@
 and Postlethwaite, 1st Edition.
 """
 
+import os
+
 import numpy as np
 import matplotlib.pyplot as plt
 
@@ -99,4 +101,5 @@
 plt.legend()
 plt.title('Disturbance response')
 
-plt.show()
+if 'PYCONTROL_TEST_EXAMPLES' not in os.environ():
+    plt.show()
