Fixing up examples for new API

Author: tkralphs

examples/DrawPolyhedron.py

@@ -0,0 +1,88 @@
+try:
+    from src.grumpy.polyhedron2D import Polyhedron2D, Figure
+except ImportError:
+    from coinor.grumpy.polyhedron2D import Polyhedron2D, Figure
+
+CYLP_INSTALLED = True
+try:
+    import numpy as np
+    from cylp.cy import CyClpSimplex
+    from cylp.py.modeling import CyLPArray, CyLPModel
+except ImportError:
+    CYLP_INSTALLED = False
+    
+import MIP4 as LP
+
+def disp_polyhedron(A = None, b = None, points = None, rays = None, c = None, obj_val = None,
+                    opt = None, loc = None):
+    if loc is None and opt is not None:
+        loc = opt
+    f = Figure()
+    f.add_polyhedron(p, label = 'Polyhedron $P$', color = 'red')
+    f.set_xlim([p.xlim[0], p.xlim[1]+1])
+    f.set_ylim([p.ylim[0], p.ylim[1]+2])
+    if c is not None and obj_val is not None:
+        f.add_line(c, obj_val, p.xlim + [0.2, 0.8], p.ylim + [0.2, 1.8], 
+                   linestyle = 'dashed', color = 'black', label = "Objective Function")
+    if opt is not None:
+        f.add_point(opt, 0.04, 'red')
+        f.add_text(loc, r'$x^* = %s$' % str(opt))
+    f.show()
+    
+try:
+    p = Polyhedron2D(A = LP.A + [[-1, 0], [0, -1]], b = LP.b + [0, 0])
+except AttributeError:
+    try:
+        p = Polyhedron2D(points = LP.points, rays = LP.rays)
+    except AttributeError:
+        print 'Error: Must specify either A and b or points and rays'
+        p = None
+
+if p is not None:
+
+    if CYLP_INSTALLED:
+        lp = CyClpSimplex()
+        
+        A = np.matrix(p.hrep.A)
+        b = CyLPArray(p.hrep.b)
+                
+        print A
+        print b
+    
+        disp_polyhedron(A = A, b = b)
+    
+        x = lp.addVariable('x', LP.numVars)
+            
+        lp += A * x <= b
+        lp += x >= 0
+    
+        c = CyLPArray(LP.c)
+        # We are maximizing, so negate objective
+        lp.objective = -c * x
+        lp.logLevel = 0
+        lp.primal(startFinishOptions = 'x')
+        np.set_printoptions(precision = 2, linewidth = 200)
+        print 'Basic variables: ', lp.basicVariables
+        print "Current tableaux and reduced costs:"
+        print lp.reducedCosts
+        print np.around(lp.tableau, decimals = 3)
+        print 'Right-hand side of optimal tableaux:'
+        #There is a bug in CyLP and this is wrong
+        #print lp.rhs
+        print np.dot(lp.basisInverse, lp.constraintsUpper)
+        print 'Inverse of optimal basis:'
+        print np.around(lp.basisInverse, 3)
+        obj_val = -lp.objectiveValue
+        psol = np.around(lp.primalVariableSolution['x'], 2)
+        print 'Optimal Value:', obj_val
+        print 'Primal solution:', psol
+        print 'Dual solution:', lp.dualConstraintSolution['R_1']
+    
+        disp_polyhedron(A = A, b = b, c = c, obj_val = obj_val,
+                        opt = psol.tolist(), loc = (psol[0]+0.1, psol[1]-0.1))
+    else:
+        print LP.A
+        print LP.b
+    
+        disp_polyhedron(A = p.hrep.A, b = p.hrep.b)
+     

examples/MIP2.py

@@ -1,5 +1,4 @@
 numVars = 2
-numCons = 3
 '''
 A = [[-2, -3], 
      [-4, -2], 
@@ -34,29 +33,9 @@
      0, 
      0]
 
-integerIndices = [0, 1]
-
-c = [20,
-     15,
+c = [-20,
+     -15,
      ]
 
 obj_val = 100
 
-sense = ('Min', '<=')
-
-points = None
-rays = []
-
-cuts = [[-4.8, -4.4], 
-        [-1, -1],
-        [-2, -1],
-        [-3, -2],
-        [-2, -1],
-        ]
-
-rhs = [-26, 
-       -6, 
-       -8,
-       -14,
-       -10, 
-       ]

examples/MIP3.py

@@ -0,0 +1,8 @@
+numVars = 2
+A = [[-9, 5],
+     [1, -13],
+     [5, -1],
+     [-1, 5]]
+#b = [0, 0, 32, 20]
+b = [0, 0, 16, 10]
+c = [1, 1]

examples/Dippy.py src/grumpy/examples/Dippy.pyexamples/Dippy.py renamed to src/grumpy/examples/Dippy.py

@@ -0,0 +1,10 @@
+numVars = 2
+#points = [[0, 0], [2, 2], [3.75, 2.75], [3, 1]]
+#rays = []
+A = [[-1, 1],
+     [1, -3],
+     [7, -3],
+     [-3, 7]]
+b = [0, 0, 18, 8]
+c = [1, 1]
+

src/grumpy/examples/DrawPolyhedron.py

@@ -1,11 +1,9 @@
+numVars = 2
 #points = [[0, 0], [3, 4], [8, 6], [6, 1]]
-points = None
-rays = []
+#rays = []
 A = [[-4, 3],
      [1, -6],
      [5, -2],
      [-2, 5]]
 b = [0, 0, 28, 14]
-#c = [1, 1]
-cuts = None
-rhs = None
+c = [1, 1]

examples/MIP1.py src/grumpy/examples/LP1.pyexamples/MIP1.py renamed to src/grumpy/examples/LP1.py

@@ -1,12 +1,9 @@
+numVars = 2
 points = [[2.5, 4.5], [6.5, 0.5], [0.5, 1],
           [7, 5.7], [7.7, 5], [2, 0.25]]
 #points = [[0, 0], [2.5, 4.5], [7.75, 5.75], [6.5, 0.5]]
 #points = [[0, 0], [2.5, 4.5], [7.5, 5.5], [6.5, 0.5]]
 rays = []
-A = None
-b = None
 c = [1,-1]
 opt = (6.5, 0.5)
 obj_val = 6
-cuts = None
-rhs = None