Mention that we use Z-polyhedra

[linpy.git] / examples / squares.py

diff --git a/examples/squares.py b/examples/squares.py
index 7f1aa30..1a0cedb 100755 (executable)
--- a/examples/squares.py
+++ b/examples/squares.py
@@ -1,21 +1,57 @@
 #!/usr/bin/env python3
 
 #!/usr/bin/env python3
 

-from pypol import *
-
-x, y = symbols('x y')
-
-sq1 = Le(0, x) & Le(x, 2) & Le(0, y) & Le(y, 2)
-sq2 = Le(2, x) & Le(x, 4) & Le(2, y) & Le(y, 4)
-
-print('sq1 =', sq1)
-print('sq2 =', sq2)
-print()
-print('¬sq1 =', ~sq1)
-print()
-print('sq1 - sq2 =', sq1 - sq2)
-print('sq1 - sq2 =', Polyhedron(sq1 - sq2))
-print()
-print('sq1 ∩ sq2 =', sq1 & sq2)
-print('sq1 ∪ sq2 =', sq1 | sq2)
-print()
-print('sq1 ⊔ sq2 =', Polyhedron(sq1 | sq2))
+# This is the code example used in the tutorial. It shows how to define and
+# manipulate polyhedra.
+
+import code
+
+
+class InteractiveConsole(code.InteractiveConsole):
+    def push(self, line=''):
+        if line:
+            print('>>>', line)
+            return super().push(line)
+        else:
+            print()
+
+
+if __name__ == '__main__':
+
+    shell = InteractiveConsole()
+
+    shell.push('from linpy import *')
+    shell.push("x, y = symbols('x y')")
+    shell.push()
+
+    shell.push('square1 = Le(0, x, 2) & Le(0, y, 2)')
+    shell.push('square1')
+    shell.push()
+
+    shell.push("square2 = Polyhedron('1 <= x <= 3, 1 <= y <= 3')")
+    shell.push('square2')
+    shell.push()
+
+    shell.push('inter = square1.intersection(square2) # or square1 & square2')
+    shell.push('inter')
+    shell.push()
+
+    shell.push('hull = square1.convex_union(square2)')
+    shell.push('hull')
+    shell.push()
+
+    shell.push('proj = square1.project([y])')
+    shell.push('proj')
+    shell.push()
+
+    shell.push('inter <= square1')
+    shell.push('inter == Empty')
+    shell.push()
+
+    shell.push('union = square1.union(square2) # or square1 | square2')
+    shell.push('union')
+    shell.push('union <= hull')
+    shell.push()
+
+    shell.push('diff = square1.difference(square2) # or square1 - square2')
+    shell.push('diff')
+    shell.push('~square1')