Merge pull request #483 from SpiNNakerManchester/neo_database

Ability to create a slice for String

pacman/model/graphs/common/slice.py

@@ -124,4 +124,25 @@ def __str__(self):
         value = ""
         for slice in self.slices:
             value += f"({slice.start}:{slice.stop})"
-        return f"[{value}]"
+        return f"{self.lo_atom}{value}"
+
+    @classmethod
+    def from_string(cls, str):
+        if str[0] == "(":
+            parts = str[1:-1].split(":")
+            lo_atom = int(parts[0])
+            hi_atom = int(parts[1])
+            return Slice(lo_atom, hi_atom)
+        parts = str.split("(")
+        lo_atom = int(parts[0])
+        shape = []
+        start = []
+        size = 1
+        for part in parts[1:]:
+            subs = part.split(":")
+            begin = int(subs[0])
+            atoms = int(subs[1][:-1]) - begin
+            size *= atoms
+            shape.append(atoms)
+            start.append(begin)
+        return Slice(lo_atom, lo_atom + size - 1, tuple(shape), tuple(start))

unittests/model_tests/test_slice.py

@@ -31,6 +31,8 @@ def test_basic(self):
         assert s.hi_atom == 10  # As specified
         assert s.as_slice == slice(0, 11)  # Slice object supported by arrays
         self.assertEqual("(0:10)", str(s))
+        s2 = Slice.from_string(str(s))
+        self.assertEqual(s, s2)
 
     def test_check_lo_atom_sanity(self):
         # Check for value sanity
@@ -80,5 +82,25 @@ def test_immutability_as_slice(self):
             s.as_slice = slice(2, 10)
 
     def test_2d(self):
-        s = Slice(0, 10, (3, 3), (0, 6))
-        self.assertEqual("[(0:3)(6:9)]", str(s))
+        s = Slice(0, 8, (3, 3), (0, 0))
+        self.assertEqual("0(0:3)(0:3)", str(s))
+        s2 = Slice.from_string(str(s))
+        self.assertEqual(s, s2)
+
+    def test_2a(self):
+        s = Slice(36, 44, (3, 3), (0, 6))
+        self.assertEqual("36(0:3)(6:9)", str(s))
+        s2 = Slice.from_string(str(s))
+        self.assertEqual(s, s2)
+
+    def test_2b(self):
+        s = Slice(9, 17, (3, 3), (3, 0))
+        self.assertEqual("9(3:6)(0:3)", str(s))
+        s2 = Slice.from_string(str(s))
+        self.assertEqual(s, s2)
+
+    def test_3b(self):
+        s = Slice(432, 455, (2, 3, 4), (6, 9, 16))
+        self.assertEqual("432(6:8)(9:12)(16:20)", str(s))
+        s2 = Slice.from_string(str(s))
+        self.assertEqual(s, s2)