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

@@ -10,6 +10,7 @@ from matplotlib.ticker import MaxNLocator
 import numpy as np
 from scipy import interpolate
 import sys
+import io
 
 from b_asic.signal_flow_graph import SFG
 from b_asic.graph_component import GraphID
@@ -180,7 +181,7 @@ class Schema:
                 self._start_times[output.graph_id] = self._start_times[source_port.operation.graph_id] + source_port.latency_offset
         self._remove_delays()
 
-    def plot_schedule(self) -> None:
+    def _plot_schedule(self):
         def _draw_arrow2(start, end):
             if end[0] < start[0]: # Wrap around
                 plt.plot([start[0], self._schedule_time], [start[1], start[1]])
@@ -223,7 +224,6 @@ class Schema:
         ypos = 0.5
         ytickpositions = []
         yticklabels = []
-        plt.figure()
         plt.grid(zorder=0.5)
         ypositions = dict()
         for op_id, op_start_time in self._start_times.items():
@@ -263,4 +263,15 @@ class Schema:
         plt.gca().xaxis.set_major_locator(MaxNLocator(integer=True))
         plt.plot([0, 0], [0, ypos], linestyle='--', color='black')
         plt.plot([self._schedule_time, self._schedule_time], [0, ypos], linestyle='--', color='black')
+
+    def plot_schedule(self) -> None:
+        plt.figure()
+        self._plot_schedule()
         plt.show()
+
+    def _repr_svg_(self):
+        self._plot_schedule()
+        f = io.StringIO()
+        plt.savefig(f, format='svg')
+
+        return f.getvalue()