def bootstrap(factor_names, model, run_count):
"""Create a minimal starting design that is non-singular."""
md = ModelDesc.from_formula(model)
model_size = len(md.rhs_termlist)
if run_count == 0:
run_count = model_size
if model_size > run_count:
raise ValueError("Can't build a design of size {} "
"for a model of rank {}. "
"Model: '{}'".format(run_count, model_size, model))
factor_count = len(factor_names)
x0 = np.zeros(factor_count)
# add high/low bounds to constraint matrix
constraint_matrix = np.zeros((factor_count * 2, factor_count))
bounds = np.zeros(factor_count * 2)
c = 0
for f in range(factor_count):
constraint_matrix[c][f] = -1
bounds[c] = 1
c += 1
constraint_matrix[c][f] = 1
bounds[c] = 1
c += 1
start_points = hit_and_run(x0, constraint_matrix, bounds, run_count)
d = pd.DataFrame(start_points, columns=factor_names)
X = dmatrix(model, d)
return (d, X)
def test_hit_and_run_one_dim(cls):
"""Tests generation of 2 points with thin = 2."""
x0 = np.array([0.5])
A = np.array([[1], [-1]])
bounds = np.array([1, 0])
np.random.seed(300)
result = hit_and_run(x0, A, bounds, 2, 2)
answer = np.array([[0.70922430], [0.59920946]])
np.testing.assert_almost_equal(result, answer)
def test_hit_and_run_constrained(cls):
"""Tests generation of 4 points."""
x0 = np.array([0.5, 0.5])
A = np.array([[1, 0], [0, 1], [-1, 0], [0, -1], [-1, -1]])
bounds = np.array([1, 1, 0, 0, -0.9])
np.random.seed(200)
result = hit_and_run(x0, A, bounds, 4, 1)
answer = np.array([[0.28429647, 0.78408962], [0.26194012, 0.99263893],
[0.30624997, 0.89710025], [0.41753565, 0.74949495]])
np.testing.assert_almost_equal(result, answer)
def test_hit_and_run_4(self):
"""Tests generation of 3 points with thin = 3."""
result = hit_and_run(self.x0, self.A, self.bounds, 2, 3)
answer = np.array([[0.32222719, 0.10867805], [0.30750317, 0.05997018]])
np.testing.assert_almost_equal(result, answer)
def test_hit_and_run_3(self):
"""Tests generation of 3 points."""
result = hit_and_run(self.x0, self.A, self.bounds, 2, 1)
answer = np.array([[0.57548241, 0.62646417], [0.77956909, 0.17414724]])
np.testing.assert_almost_equal(result, answer)
def test_hit_and_run_2(self):
"""Tests generation of a single point with thin = 3."""
result = hit_and_run(self.x0, self.A, self.bounds, 1, 3)
answer = np.array([[0.32222719, 0.10867805]])
np.testing.assert_almost_equal(result, answer)
def test_hit_and_run_1(self):
"""Tests generation of a single point."""
result = hit_and_run(self.x0, self.A, self.bounds, 1, 1)
answer = np.array([[0.57548241, 0.62646417]])
np.testing.assert_almost_equal(result, answer)