def inflate_region(obstacle_pts, A_bounds, b_bounds, start, require_containment=False, iter_limit=np.inf):
A_bounds = np.array(A_bounds)
b_bounds = np.array(b_bounds)
d = np.array(start)
dim = A_bounds.shape[1]
C = 0.01 * np.eye(dim)
best_vol = 1e-100
results = {'p_history': [], 'e_history': []}
iters = 1
while True:
A, b, infeas_start = compute_obstacle_planes(obstacle_pts, C, d)
# print "number of hyperplanes:", len(b)
A = np.vstack((A, A_bounds))
b = np.hstack((b, b_bounds))
if require_containment:
if np.all(A.dot(start) <= b) or iters == 1 or infeas_start:
results['p_history'].append({'A': A, 'b': b})
else:
A = results['p_history'][-1]['A']
b = results['p_history'][-1]['b']
# print "Breaking early because start point is no longer contained in polytope"
break
else:
results['p_history'].append({'A': A, 'b': b})
iters += 1
if iters > iter_limit:
# print "iter limit reached"
break
try:
C, d = lownerjohn_inner(A, b)
except mosek.fusion.SolutionError:
print "Breaking early beause ellipsoid maximization failed"
break
C = np.array(C)
d = np.array(d)
vol = np.linalg.det(C)
results['e_history'].append({'C': C, 'd': d})
if abs(vol - best_vol) / best_vol < 2e-2:
break
best_vol = vol
return A, b, C, d, results
from scipy.io import loadmat, savemat
from irispy.mosek_ellipsoid.lownerjohn_ellipsoid import lownerjohn_inner
"""
MATLAB wrapper to the python lownerjohn_inner function (the MATLAB interface to Mosek Fusion fails after any call to 'clear java', so we can use this interface instead).
usage:
python -m irispy.mosek.matlab_wrapper fname
where fname is a .mat file containing matrix A and vector b. Results will be stored in the same file.
Example usage from MATLAB:
function [C, d] = py_lownerjohn_inner(A, b)
fname = tempname();
save(fname, 'A', 'b');
system(['python -m irispy.mosek.matlab_wrapper ', fname]);
load(fname, 'C', 'd');
d = reshape(d, [], 1);
end
"""
fname = sys.argv[1]
matvars = loadmat(fname, mat_dtype=True)
A = matvars['A']
b = matvars['b'].reshape((-1))
[C, d] = lownerjohn_inner(A, b);
savemat(fname, {'C': C, 'd': d})
