Better schedule, including plotting

• plot_schedule method that plots the schedule
• forward_slack and backward_slack
• Execution times supported
• Slightly different graph_id that more often do not change the previous
• scipy is now a dependency for drawing splines

Close #35 (closed)

b_asic/schema.py

@@ -14,7 +14,6 @@ import io
 
 from b_asic.signal_flow_graph import SFG
 from b_asic.graph_component import GraphID
-from b_asic.operation import Operation
 from b_asic.special_operations import Delay, Output
 
 
@@ -108,6 +107,22 @@ class Schema:
     def schedule_time(self) -> int:
         return self._schedule_time
 
+    def increase_time_resolution(self, factor: int) -> None:
+        raise NotImplementedError
+
+    def decrease_time_resolution(self, factor: int) -> None:
+        raise NotImplementedError
+
+    def move_operation(self, op_id: GraphID, time: int) -> None:
+        assert op_id in self._start_times, "No operation with the specified op_id in this schema."
+        if time < 0:
+            if -time > self.backward_slack(op_id):
+                raise ValueError
+        else:
+            if time > self.forward_slack(op_id):
+                raise ValueError
+        self._start_times[op_id] += time
+
     def _remove_delays(self) -> None:
         delay_list = self._sfg.find_by_type_name(Delay.type_name())
         while delay_list:
@@ -270,6 +285,7 @@ class Schema:
         plt.show()
 
     def _repr_svg_(self):
+        plt.figure()
         self._plot_schedule()
         f = io.StringIO()
         plt.savefig(f, format='svg')