class TestFitter(unittest.TestCase):
def setUp(self):
self.xdata = np.linspace(-4, 4, 100)
self.p0 = np.array([0., 1., 0.0, 1.])
self.bounds = [(-1, 1), (0, 2), (-1, 1.), (0.001, 2)]
self.params = curvefitter.to_parameters(self.p0 + 0.2,
bounds=self.bounds)
self.final_params = curvefitter.to_parameters(self.p0,
bounds=self.bounds)
self.ydata = gauss(self.xdata, self.final_params)
self.f = CurveFitter(gauss, (self.xdata, self.ydata), self.params)
def test_fitting(self):
# the simplest test - a really simple gauss curve with perfect data
res = self.f.fit()
assert_almost_equal(values(res.params), self.p0)
assert_almost_equal(res.chisqr, 0)
def test_NIST(self):
# Run all the NIST standard tests with leastsq
for model in Models:
try:
NIST_runner(model)
except Exception:
print(model)
raise
def test_model_returns_function(self):
ydata = gauss(self.xdata, self.final_params)
model = self.f.model(self.final_params)
assert_almost_equal(ydata, model)
def test_residuals(self):
resid = self.f.residuals(self.final_params)
assert_almost_equal(np.sum(resid**2), 0)
def test_cost(self):
resid = self.f.residuals(self.final_params)
assert_almost_equal(0, np.sum(resid**2))
def test_leastsq(self):
# test that a custom method can be used with scipy.optimize.minimize
res = self.f.fit()
assert_almost_equal(values(res.params), self.p0)
def test_resid_length(self):
# the residuals length should be equal to the data length
resid = self.f.residuals(self.params)
assert_equal(resid.size, self.f.dataset.y.size)
def test_scalar_minimize(self):
assert_equal(values(self.params), self.p0 + 0.2)
res = self.f.fit(method='differential_evolution')
assert_almost_equal(values(res.params), self.p0, 3)
def test_holding_parameter(self):
# holding parameters means that those parameters shouldn't change
# during a fit
self.params['p0'].vary = False
res = self.f.fit()
assert_almost_equal(self.p0[0] + 0.2, self.params['p0'].value)
assert_almost_equal(res.params['p0'].value, self.params['p0'].value)
def test_fit_returns_MinimizerResult(self):
self.params['p0'].vary = False
res = self.f.fit()
assert_(isinstance(res, MinimizerResult))
def test_costfun(self):
# test user defined costfun
res = self.f.fit('nelder')
def costfun(params, generative, y, e):
return np.sum((y - generative / e) ** 2)
g = CurveFitter(gauss,
(self.xdata, self.ydata),
self.params,
costfun=costfun)
res2 = g.fit('nelder')
assert_almost_equal(values(res.params), values(res2.params))
def test_args_kwds_are_used(self):
# check that user defined args and kwds make their way into the user
# function
a = [1., 2.]
x = np.linspace(0, 10, 11)
y = a[0] + 1 + 2 * a[1] * x
par = Parameters()
par.add('p0', 1.5)
par.add('p1', 2.5)
def fun(x, p, *args, **kwds):
assert_equal(args, a)
return args[0] + p['p0'] + p['p1'] * a[1] * x
g = CurveFitter(fun, (x, y), par, fcn_args=a)
res = g.fit()
assert_almost_equal(values(res.params), [1., 2.])
d = {'a': 1, 'b': 2}
def fun(x, p, *args, **kwds):
return kwds['a'] + p['p0'] + p['p1'] * kwds['b'] * x
g = CurveFitter(fun, (x, y), par, fcn_kws=d)
res = g.fit()
assert_almost_equal(values(res.params), [1., 2.])
def test_multipledataset_corefinement(self):
# test corefinement of three datasets
e361 = np.loadtxt(os.path.join(CURDIR, 'e361r.txt'))
e365 = np.loadtxt(os.path.join(CURDIR, 'e365r.txt'))
e366 = np.loadtxt(os.path.join(CURDIR, 'e366r.txt'))
coefs361 = np.zeros(16)
coefs361[0] = 2
coefs361[1] = 1.
coefs361[2] = 2.07
coefs361[4] = 6.36
coefs361[6] = 2e-5
coefs361[7] = 3
coefs361[8] = 10
coefs361[9] = 3.47
coefs361[11] = 4
coefs361[12] = 200
coefs361[13] = 1
coefs361[15] = 3
coefs365 = np.copy(coefs361)
coefs366 = np.copy(coefs361)
coefs365[4] = 3.47
coefs366[4] = -0.56
qvals361, rvals361, evals361 = np.hsplit(e361, 3)
qvals365, rvals365, evals365 = np.hsplit(e365, 3)
qvals366, rvals366, evals366 = np.hsplit(e366, 3)
lowlim = np.zeros(16)
lowlim[4] = -0.8
hilim = 2 * coefs361
bounds = list(zip(lowlim, hilim))
params361 = curvefitter.to_parameters(coefs361,
bounds=bounds,
varies=[False] * 16)
params365 = curvefitter.to_parameters(coefs365,
bounds=bounds,
varies=[False] * 16)
params366 = curvefitter.to_parameters(coefs366,
bounds=bounds,
varies=[False] * 16)
assert_(len(params361), 16)
assert_(len(params365), 16)
assert_(len(params366), 16)
fit = [1, 6, 8, 12, 13]
for p in fit:
params361['p%d' % p].vary = True
params365['p%d' % p].vary = True
params366['p%d' % p].vary = True
a = CurveFitter(reflect_fitfunc,
(qvals361.flatten(), np.log10(rvals361.flatten())),
params361)
b = CurveFitter(reflect_fitfunc,
(qvals365.flatten(), np.log10(rvals365.flatten())),
params365)
c = CurveFitter(reflect_fitfunc,
(qvals366.flatten(), np.log10(rvals366.flatten())),
params366)
g = GlobalFitter([a, b, c], constraints=['d1:p8=d0:p8',
'd2:p8=d0:p8',
'd1:p12=d0:p12',
'd2:p12 = d0:p12'],
kws={'seed': 1})
indiv_chisqr = (a.residuals(a.params) ** 2 +
b.residuals(b.params) ** 2 +
c.residuals(c.params) ** 2)
global_chisqr = g.residuals(g.params) ** 2
assert_almost_equal(indiv_chisqr.sum(), global_chisqr.sum())
# import time
res = g.fit('differential_evolution')
# start = time.time()
# g.emcee(params=res.params, nwalkers=300, steps=500, workers=1)
# finish = time.time()
# print(finish - start)
assert_almost_equal(res.chisqr, 0.774590447535, 4)
# updating of constraints should happen during the fit
assert_almost_equal(a.params['p12'].value, res.params['p12_d0'].value)
assert_almost_equal(b.params['p12'].value, a.params['p12'].value)
assert_almost_equal(c.params['p12'].value, a.params['p12'].value)
g.params['p8_d0'].value = 10.123456
# shouldn't need to call update constraints within the gfitter, that
# happens when you retrieve a specific value
assert_almost_equal(g.params['p8_d1'].value, g.params['p8_d0'].value)
# However, you have to call model or residuals to redistribute the
# parameters to the original fitters
g.model()
assert_almost_equal(a.params['p8'].value, 10.123456)
assert_almost_equal(b.params['p8'].value, 10.123456)
def test_multipledataset_corefinement(self):
# test corefinement of three datasets
e361 = np.loadtxt(os.path.join(CURDIR, 'e361r.txt'))
e365 = np.loadtxt(os.path.join(CURDIR, 'e365r.txt'))
e366 = np.loadtxt(os.path.join(CURDIR, 'e366r.txt'))
coefs361 = np.zeros(16)
coefs361[0] = 2
coefs361[1] = 1.
coefs361[2] = 2.07
coefs361[4] = 6.36
coefs361[6] = 2e-5
coefs361[7] = 3
coefs361[8] = 10
coefs361[9] = 3.47
coefs361[11] = 4
coefs361[12] = 200
coefs361[13] = 1
coefs361[15] = 3
coefs365 = np.copy(coefs361)
coefs366 = np.copy(coefs361)
coefs365[4] = 3.47
coefs366[4] = -0.56
qvals361, rvals361, evals361 = np.hsplit(e361, 3)
qvals365, rvals365, evals365 = np.hsplit(e365, 3)
qvals366, rvals366, evals366 = np.hsplit(e366, 3)
lowlim = np.zeros(16)
lowlim[4] = -0.8
hilim = 2 * coefs361
bounds = list(zip(lowlim, hilim))
params361 = curvefitter.to_parameters(coefs361, bounds=bounds,
varies=[False] * 16)
params365 = curvefitter.to_parameters(coefs365, bounds=bounds,
varies=[False] * 16)
params366 = curvefitter.to_parameters(coefs366, bounds=bounds,
varies=[False] * 16)
assert_(len(params361), 16)
assert_(len(params365), 16)
assert_(len(params366), 16)
fit = [1, 6, 8, 12, 13]
for p in fit:
params361['p%d' % p].vary = True
params365['p%d' % p].vary = True
params366['p%d' % p].vary = True
a = CurveFitter(reflect_fitfunc, qvals361.flatten(),
np.log10(rvals361.flatten()),
params361)
b = CurveFitter(reflect_fitfunc, qvals365.flatten(),
np.log10(rvals365.flatten()),
params365)
c = CurveFitter(reflect_fitfunc, qvals366.flatten(),
np.log10(rvals366.flatten()),
params366)
g = GlobalFitter([a, b, c], constraints=['d1:p8=d0:p8',
'd2:p8=d0:p8',
'd1:p12=d0:p12',
'd2:p12 = d0:p12'],
kws={'seed':1})
indiv_chisqr = (a.residuals(a.params) ** 2
+ b.residuals(b.params) ** 2
+ c.residuals(c.params) ** 2)
global_chisqr = g.residuals(g.params) ** 2
assert_almost_equal(indiv_chisqr.sum(), global_chisqr.sum())
# import time
res = g.fit('differential_evolution')
# start = time.time()
# g.emcee(params=res.params, nwalkers=300, steps=500, workers=1)
# finish = time.time()
# print(finish - start)
assert_almost_equal(res.chisqr, 0.774590447535, 4)
class TestFitter(unittest.TestCase):
def setUp(self):
self.xdata = np.linspace(-4, 4, 100)
self.p0 = np.array([0., 1., 0.0, 1.])
self.bounds = [(-1, 1), (0, 2), (-1, 1.), (0.001, 2)]
self.params = curvefitter.to_parameters(self.p0 + 0.2, bounds=self.bounds)
self.final_params = curvefitter.to_parameters(self.p0, bounds=self.bounds)
self.ydata = gauss(self.xdata, self.final_params)
self.f = CurveFitter(gauss, (self.xdata, self.ydata), self.params)
def pvals(self, params):
return np.asfarray(list(params.valuesdict().values()))
def test_fitting(self):
# the simplest test - a really simple gauss curve with perfect data
res = self.f.fit()
assert_almost_equal(self.pvals(res.params), self.p0)
assert_almost_equal(res.chisqr, 0)
def test_NIST(self):
# Run all the NIST standard tests with leastsq
for model in Models.keys():
try:
NIST_runner(model)
except Exception:
print(model)
raise
def test_model_returns_function(self):
ydata = gauss(self.xdata, self.final_params)
model = self.f.model(self.final_params)
assert_almost_equal(ydata, model)
def test_residuals(self):
resid = self.f.residuals(self.final_params)
assert_almost_equal(np.sum(resid**2), 0)
def test_cost(self):
resid = self.f.residuals(self.final_params)
assert_almost_equal(0, np.sum(resid**2))
def test_leastsq(self):
# test that a custom method can be used with scipy.optimize.minimize
res = self.f.fit()
assert_almost_equal(self.pvals(res.params), self.p0)
def test_resid_length(self):
# the residuals length should be equal to the data length
resid = self.f.residuals(self.params)
assert_equal(resid.size, self.f.ydata.size)
def test_scalar_minimize(self):
assert_equal(self.pvals(self.params), self.p0 + 0.2)
res = self.f.fit(method='differential_evolution')
assert_almost_equal(self.pvals(res.params), self.p0, 3)
def test_holding_parameter(self):
# holding parameters means that those parameters shouldn't change
# during a fit
self.params['p0'].vary = False
res = self.f.fit()
assert_almost_equal(self.p0[0] + 0.2, self.params['p0'].value)
def test_fit_returns_MinimizerResult(self):
self.params['p0'].vary = False
res = self.f.fit()
assert_(isinstance(res, MinimizerResult))
def test_costfun(self):
# test user defined costfun
res = self.f.fit('nelder')
def costfun(params, generative, y, e):
return np.sum((y - generative / e) ** 2)
g = CurveFitter(gauss, (self.xdata, self.ydata), self.params, costfun=costfun)
res2 = g.fit('nelder')
assert_almost_equal(self.pvals(res.params), self.pvals(res2.params))
