def simplify(x, y, maxpoints=20):
x = map(float, x)
y = map(float, y)
pts = np.array(zip(x, y))
simplifier = VWSimplifier(pts)
sqd = []
iter_range = range(2, maxpoints + 1)
for i in iter_range:
VWpts = simplifier.from_number(i)
xn, yn = zip(*VWpts)
out = np.sum((y - np.interp(x, xn, yn))**2)
sqd.append(out)
# sqd /= max(sqd)
if min(sqd) == max(sqd):
VWpts = simplifier.from_number(2)
return VWpts
else:
sqd = rescale(sqd)
# plt.plot(sqd)
# plt.show()
# iter = (np.array(iter_range) - 2) / (maxpoints - 2.)
# plt.plot(iter_range, sqd, label='residual')
# plt.plot(iter_range, iter, color='r', label='iteration')
# plt.plot(iter_range, iter + sqd, color='g', label='residual+iteration')
# plt.legend(loc='upper center', shadow=True)
# plt.show()
# npoints = np.argmin(iter + sqd) + 2
npoints = np.argmax(np.array(sqd) < 0.01) + 2
VWpts = simplifier.from_number(npoints)
return VWpts
def test_rescale():
assert anc.rescale([1000, 2000, 3000], [1, 3]) == [1, 2, 3]
with pytest.raises(RuntimeError):
anc.rescale([1000, 1000])