def test_removeVar2(self):
s = CyClpSimplex()
fp = os.path.join(currentFilePath, '../../input/p0033.mps')
s.extractCyLPModel(fp)
y = s.addVariable('y', 3)
s.primal()
x = s.getVarByName('x')
s.addConstraint(x[1] + y[1] >= 1.2)
#s.primal()
s.removeVariable('x')
s.primal()
s = s.primalVariableSolution
self.assertTrue((s['y'] - np.array([0, 1.2, 0]) <= 10**-6).all())
def __init__(self,
module_name=None,
file_name=None,
A=None,
b=None,
c=None,
points=None,
rays=None,
l=None,
u=None,
sense=None,
integerIndices=None,
numVars=None):
if file_name is not None:
# We got a file name, so ignore everything else and read in the instance
lp = CyClpSimplex()
lp.extractCyLPModel(file_name)
self.integerIndices = [
i for (i, j) in enumerate(lp.integerInformation) if j == True
]
infinity = lp.getCoinInfinity()
self.A = lp.coefMatrix
self.b = CyLPArray([0 for _ in range(lp.nRows)])
for i in range(lp.nRows):
if lp.constraintsLower[i] > -infinity:
if lp.constraintsUpper[i] < infinity:
raise Exception('Cannot handle ranged constraints')
self.b[i] = -lp.constraintsLower[i]
for j in range(lp.nCols):
self.A[i, j] = -self.A[i, j]
elif lp.constraintsUpper[i] < infinity:
self.b[i] = lp.constraintsUpper[i]
else:
raise Exception('Constraint with no bounds detected')
#x = lp.addVariable('x', lp.nCols)
#lp += A * x <= b
#lp += x <= lp.variablesUpper
#lp += x >= lp.variablesLower
#lp.objective = lp.objective
self.c = lp.objective
self.sense = '<='
numVars = lp.nCols
self.lp = lp
self.l = lp.variablesLower
self.u = lp.variablesUpper
self.x = lp.getVarByName('x')
else:
min_or_max = None
if module_name is not None:
# We got a module name, read the data from there
mip = ilib.import_module(module_name)
self.A = mip.A if hasattr(mip, 'A') else None
self.b = mip.b if hasattr(mip, 'b') else None
points = mip.points if hasattr(mip, 'points') else None
rays = mip.rays if hasattr(mip, 'rays') else None
self.c = mip.c if hasattr(mip, 'c') else None
self.sense = mip.sense[1] if hasattr(mip, 'sense') else None
min_or_max = mip.sense[0] if hasattr(mip, 'sense') else None
self.integerIndices = mip.integerIndices if hasattr(
mip, 'integerIndices') else None
self.u = CyLPArray(mip.u) if hasattr(mip, 'u') else None
self.l = CyLPArray(mip.l) if hasattr(mip, 'l') else None
numVars = mip.numVars if hasattr(mip, 'numVars') else None
self.x_sep = mip.x_sep if hasattr(mip, 'x_sep') else None
if numVars is None and mip.A is not None:
numVars = len(mip.A)
if numVars is None:
raise "Must specify number of variables when problem is not"
else:
self.A = A
self.b = b
self.c = c
self.l = l
self.u = u
self.points = points
self.rays = rays
if sense is not None:
self.sense = sense[1]
min_or_max = sense[0]
self.integerIndices = integerIndices
lp = CyClpSimplex()
if self.A is not None:
A = np.matrix(self.A)
b = CyLPArray(self.b)
elif numVars <= 2 and GRUMPY_INSTALLED:
p = Polyhedron2D(points=points, rays=rays)
A = np.matrix(p.hrep.A)
b = np.matrix(p.hrep.b)
else:
raise "Must specify problem in inequality form with more than two variables\n"
x = lp.addVariable('x', numVars)
if l is not None:
lp += x >= l
if u is not None:
lp += x <= u
lp += (A * x <= b if self.sense == '<=' else A * x >= b)
c = CyLPArray(self.c)
if min_or_max == 'Max':
lp.objective = -c * x
else:
lp.objective = c * x
self.lp = lp
self.x = x
