ZLT bugfix : If there is no rates available between acceptable and fi…

…rst dropping rate (i.e. If the current variables already do the max throughput) just skip monotonic processing

npf/expdesign/zltexp.py

@@ -56,7 +56,7 @@ def need_run_for(self, next_val):
 
     def ensure_monotonic(self, max_r, vals_for_current):
 
-        if not self.monotonic:
+        if not self.monotonic and max_r < max(self.executable_values):
             # If the function is not monotonic, we now have to try rates between the max acceptable and the first dropping rate
             after_max = next(iter(filter(lambda x : x > max_r, self.executable_values)))
             if after_max not in vals_for_current: