examples/squares.py

   1 #!/usr/bin/env python3
   2
   3 # This is the code example used in the tutorial. It shows how to define and
   4 # manipulate polyhedra.
   5
   6 import code
   7
   8
   9 class InteractiveConsole(code.InteractiveConsole):
  10     def push(self, line=''):
  11         if line:
  12             print('>>>', line)
  13             return super().push(line)
  14         else:
  15             print()
  16
  17
  18 if __name__ == '__main__':
  19
  20     shell = InteractiveConsole()
  21
  22     shell.push('from linpy import *')
  23     shell.push("x, y = symbols('x y')")
  24     shell.push()
  25
  26     shell.push('square1 = Le(0, x, 2) & Le(0, y, 2)')
  27     shell.push('square1')
  28     shell.push()
  29
  30     shell.push("square2 = Polyhedron('1 <= x <= 3, 1 <= y <= 3')")
  31     shell.push('square2')
  32     shell.push()
  33
  34     shell.push('inter = square1.intersection(square2) # or square1 & square2')
  35     shell.push('inter')
  36     shell.push()
  37
  38     shell.push('hull = square1.convex_union(square2)')
  39     shell.push('hull')
  40     shell.push()
  41
  42     shell.push('proj = square1.project([y])')
  43     shell.push('proj')
  44     shell.push()
  45
  46     shell.push('inter <= square1')
  47     shell.push('inter == Empty')
  48     shell.push()
  49
  50     shell.push('union = square1.union(square2) # or square1 | square2')
  51     shell.push('union')
  52     shell.push('union <= hull')
  53     shell.push()
  54
  55     shell.push('diff = square1.difference(square2) # or square1 - square2')
  56     shell.push('diff')
  57     shell.push('~square1')