Merge pull request #250 from adm78/bugfix/truth-value-ambiguity-in-xferfcn-evalfr

murrayrm · web-flow · commit 084e7333fde3 · 2018-12-21T14:40:19.000-08:00
Fixing bug in xferfcn._evalfr that caused ValueError for discrete systems
diff --git a/control/xferfcn.py b/control/xferfcn.py
@@ -510,7 +510,7 @@ def _evalfr(self, omega):
             # Convert the frequency to discrete time
             dt = timebase(self)
             s = exp(1.j * omega * dt)
-            if (omega * dt > pi):
+            if np.any(omega * dt > pi):
                 warn("_evalfr: frequency evaluation above Nyquist frequency")
         else:
             s = 1.j * omega
