example1b.py

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## Example adapted from examples/example1b.cpp.
## author of this file: Sebastian F. Walter

import numpy as np
from qpoases import PyQProblemB as QProblemB
from qpoases import PyBooleanType as BooleanType
from qpoases import PySubjectToStatus as SubjectToStatus
from qpoases import PyOptions as Options

# Example for qpOASES main function using the QProblemB class.

#Setup data of first QP.

H   = np.array([1.0, 0.0, 0.0, 0.5 ]).reshape((2,2))
g   = np.array([1.5, 1.0 ])
lb  = np.array([0.5, -2.0])
ub  = np.array([5.0, 2.0 ])

# Setup data of second QP.

g_new   = np.array([1.0, 1.5])
lb_new  = np.array([0.0, -1.0])
ub_new  = np.array([5.0, -0.5])


# Setting up QProblemB object.
example = QProblemB(2)

options = Options()
options.enableFlippingBounds = BooleanType.FALSE
options.initialStatusBounds  = SubjectToStatus.INACTIVE
options.numRefinementSteps   = 1

example.setOptions(options)

# Solve first QP.
nWSR = np.array([10])
example.init(H, g, lb, ub, nWSR)
print("\nnWSR = %d\n\n"%nWSR)

# Solve second QP.
nWSR = np.array([10])
example.hotstart(g_new, lb_new, ub_new, nWSR)
print("\nnWSR = %d\n\n"% nWSR)

# Get and print solution of second QP.
xOpt = np.zeros(2)
example.getPrimalSolution(xOpt)
print("\nxOpt = [ %e, %e ];  objVal = %e\n\n" %(xOpt[0], xOpt[1],
                                                    example.getObjVal()))