fix grid formatter

bnavigator · bnavigator · commit abc0c3c002b4 · 2020-08-20T21:35:47.000+02:00
diff --git a/control/grid.py b/control/grid.py
@@ -12,7 +12,7 @@
 class FormatterDMS(object):
     '''Transforms angle ticks to damping ratios'''
     def __call__(self, direction, factor, values):
-        angles_deg = values/factor
+        angles_deg = np.asarray(values)/factor
         damping_ratios = np.cos((180-angles_deg) * np.pi/180)
         ret = ["%.2f" % val for val in damping_ratios]
         return ret
