added warning if Ks are not all close to each other

devices/undulator.py

@@ -147,6 +147,15 @@ class Undulators(Adjustable):
         a = self.adjs[und_name_cal]
         k = a.get_current_value()
         energy = self.K_to_eV(k)
+
+        all_ks = [a.get_current_value() for a in self.adjs.values()]
+        checks = np.isclose(all_ks, k, rtol=0, atol=0.001)
+        if not all(checks):
+            print("Warning: Ks are not all close:")
+            for name, k, chk in zip(self.adjs.keys(), all_ks, checks):
+                if not chk:
+                    print(name, k)
+
         return float(energy) * 1000 # keV -> eV