Example #1
0
 def residual(pars, x, data=None):
     g1 = gaussian(x, pars['a1'].value, pars['c1'].value, pars['w1'].value)
     g2 = gaussian(x, pars['a2'].value, pars['c2'].value, pars['w2'].value)
     model = g1 + g2
     if data is None:
         return model
     return (model - data)
Example #2
0
 def residual(pars, x, data=None):
     g1 = gaussian(x, pars['a1'].value, pars['c1'].value, pars['w1'].value)
     g2 = gaussian(x, pars['a2'].value, pars['c2'].value, pars['w2'].value)
     model = g1 + g2
     if data is None:
         return model
     return (model - data)
Example #3
0
    def test_sum_of_two_gaussians(self):

        # two user-defined gaussians
        model1 = self.model
        f2 = lambda x, amplitude_, center_, sigma_: gaussian(
            x, amplitude_, center_, sigma_)
        model2 = Model(f2, ['x'])
        values1 = self.true_values()
        values2 = self.true_values()
        values2['sigma'] = 1.5
        data  = gaussian(x=self.x, **values1)
        data += gaussian(x=self.x, **values2)
        model = self.model + model2
        values2 = {k + '_': v for k, v in values2.items()}
        guess = {'sigma': Parameter(value=2, min=0), 'center': 1,
                 'amplitude': Parameter(value=3, min=0),
                 'sigma_': Parameter(value=1, min=0), 'center_': 1,
                 'amplitude_': Parameter(value=2.3)}

        true_values = dict(list(values1.items()) + list(values2.items()))
        result = model.fit(data, x=self.x, **guess)

        assert_results_close(result.values, true_values)

        # user-defined models with common parameter names
        # cannot be added, and should raise
        f = lambda: model1 + model1
        self.assertRaises(NameError, f)

        # two predefined_gaussians, using suffix to differentiate
        model1 = specified_models.Gaussian(['x'])
        model2 = specified_models.Gaussian(['x'], suffix='_')
        model = model1 + model2
        true_values = {'center': values1['center'],
                       'amplitude': values1['amplitude'],
                       'sigma': values1['sigma'],
                       'center_': values2['center_'],
                       'amplitude_': values2['amplitude_'],
                       'sigma_': values2['sigma_']}
        guess = {'sigma': 2, 'center': 1, 'amplitude': 1,
                 'sigma_': 1, 'center_': 1, 'amplitude_': 1}
        result = model.fit(data, x=self.x, **guess)
        assert_results_close(result.values, true_values)

        # without suffix, the names collide and Model should raise
        model1 = specified_models.Gaussian(['x'])
        model2 = specified_models.Gaussian(['x'])
        f = lambda: model1 + model2
        self.assertRaises(NameError, f)
Example #4
0
 def setUp(self):
     self.x = np.linspace(-10, 10, num=1000)
     np.random.seed(1)
     self.noise = 0.01 * np.random.randn(*self.x.shape)
     self.true_values = lambda: dict(height=7, center=1, sigma=3)
     self.guess = lambda: dict(height=5, center=2, sigma=4)
     # return a fresh copy
     self.model = Model(gaussian, ['x'])
     self.data = gaussian(x=self.x, **self.true_values()) + self.noise
Example #5
0
 def setUp(self):
     self.x = np.linspace(-10, 10, num=1000)
     np.random.seed(1)
     self.noise = 0.01*np.random.randn(*self.x.shape)
     self.true_values = lambda: dict(amplitude=7.1, center=1.1, sigma=2.40)
     self.guess = lambda: dict(amplitude=5, center=2, sigma=4)
     # return a fresh copy
     self.model = Model(gaussian, ['x'])
     self.data = gaussian(x=self.x, **self.true_values()) + self.noise
    def residual(pars, x, sigma=None, data=None):
        yg = gaussian(x, pars['amp_g'].value,
                      pars['cen_g'].value, pars['wid_g'].value)
        yl = lorentzian(x, pars['amp_l'].value,
                   pars['cen_l'].value, pars['wid_l'].value)

        slope = pars['line_slope'].value
        offset = pars['line_off'].value
        model =  yg +  yl + offset + x * slope
        if data is None:
            return model
        if sigma is None:
            return (model - data)
        return (model - data)/sigma
    def residual(pars, x, sigma=None, data=None):
        yg = gaussian(x, pars['amp_g'].value, pars['cen_g'].value,
                      pars['wid_g'].value)
        yl = loren(x, pars['amp_l'].value, pars['cen_l'].value,
                   pars['wid_l'].value)

        slope = pars['line_slope'].value
        offset = pars['line_off'].value
        model = yg + yl + offset + x * slope
        if data is None:
            return model
        if sigma is None:
            return (model - data)
        return (model - data) / sigma
def test_constraints(with_plot=True):
    with_plot = with_plot and HASPYLAB

    def residual(pars, x, sigma=None, data=None):
        yg = gaussian(x, pars['amp_g'].value, pars['cen_g'].value,
                      pars['wid_g'].value)
        yl = loren(x, pars['amp_l'].value, pars['cen_l'].value,
                   pars['wid_l'].value)

        slope = pars['line_slope'].value
        offset = pars['line_off'].value
        model = yg + yl + offset + x * slope
        if data is None:
            return model
        if sigma is None:
            return (model - data)
        return (model - data) / sigma

    n = 201
    xmin = 0.
    xmax = 20.0
    x = linspace(xmin, xmax, n)

    data = (gaussian(x, 21, 8.1, 1.2) + loren(x, 10, 9.6, 2.4) +
            random.normal(scale=0.23, size=n) + x * 0.5)

    if with_plot:
        pylab.plot(x, data, 'r+')

    pfit = [
        Parameter(name='amp_g', value=10),
        Parameter(name='cen_g', value=9),
        Parameter(name='wid_g', value=1),
        Parameter(name='amp_tot', value=20),
        Parameter(name='amp_l', expr='amp_tot - amp_g'),
        Parameter(name='cen_l', expr='1.5+cen_g'),
        Parameter(name='wid_l', expr='2*wid_g'),
        Parameter(name='line_slope', value=0.0),
        Parameter(name='line_off', value=0.0)
    ]

    sigma = 0.021  # estimate of data error (for all data points)

    myfit = Minimizer(residual,
                      pfit,
                      fcn_args=(x, ),
                      fcn_kws={
                          'sigma': sigma,
                          'data': data
                      },
                      scale_covar=True)

    myfit.prepare_fit()
    init = residual(myfit.params, x)

    myfit.leastsq()

    print(' Nfev = ', myfit.nfev)
    print(myfit.chisqr, myfit.redchi, myfit.nfree)

    report_fit(myfit.params, min_correl=0.3)

    fit = residual(myfit.params, x)
    if with_plot:
        pylab.plot(x, fit, 'b-')
    assert (myfit.params['cen_l'].value == 1.5 + myfit.params['cen_g'].value)
    assert (myfit.params['amp_l'].value == myfit.params['amp_tot'].value -
            myfit.params['amp_g'].value)
    assert (myfit.params['wid_l'].value == 2 * myfit.params['wid_g'].value)

    # now, change fit slightly and re-run
    myfit.params['wid_l'].expr = '1.25*wid_g'
    myfit.leastsq()
    report_fit(myfit.params, min_correl=0.4)
    fit2 = residual(myfit.params, x)
    if with_plot:
        pylab.plot(x, fit2, 'k')
        pylab.show()

    assert (myfit.params['cen_l'].value == 1.5 + myfit.params['cen_g'].value)
    assert (myfit.params['amp_l'].value == myfit.params['amp_tot'].value -
            myfit.params['amp_g'].value)
    assert (myfit.params['wid_l'].value == 1.25 * myfit.params['wid_g'].value)
def test_constraints2():
    """add a user-defined function to symbol table"""
    def residual(pars, x, sigma=None, data=None):
        yg = gaussian(x, pars['amp_g'].value, pars['cen_g'].value,
                      pars['wid_g'].value)
        yl = loren(x, pars['amp_l'].value, pars['cen_l'].value,
                   pars['wid_l'].value)

        slope = pars['line_slope'].value
        offset = pars['line_off'].value
        model = yg + yl + offset + x * slope
        if data is None:
            return model
        if sigma is None:
            return (model - data)
        return (model - data) / sigma

    n = 601
    xmin = 0.
    xmax = 20.0
    x = linspace(xmin, xmax, n)

    data = (gaussian(x, 21, 8.1, 1.2) + loren(x, 10, 9.6, 2.4) +
            random.normal(scale=0.23, size=n) + x * 0.5)

    pfit = [
        Parameter(name='amp_g', value=10),
        Parameter(name='cen_g', value=9),
        Parameter(name='wid_g', value=1),
        Parameter(name='amp_tot', value=20),
        Parameter(name='amp_l', expr='amp_tot - amp_g'),
        Parameter(name='cen_l', expr='1.5+cen_g'),
        Parameter(name='line_slope', value=0.0),
        Parameter(name='line_off', value=0.0)
    ]

    sigma = 0.021  # estimate of data error (for all data points)

    myfit = Minimizer(residual,
                      pfit,
                      fcn_args=(x, ),
                      fcn_kws={
                          'sigma': sigma,
                          'data': data
                      },
                      scale_covar=True)

    def width_func(wpar):
        """ """
        return 2 * wpar

    myfit.asteval.symtable['wfun'] = width_func
    myfit.params.add(name='wid_l', expr='wfun(wid_g)')

    myfit.leastsq()

    print(' Nfev = ', myfit.nfev)
    print(myfit.chisqr, myfit.redchi, myfit.nfree)

    report_fit(myfit.params)
    pfit = myfit.params
    fit = residual(myfit.params, x)
    assert (pfit['cen_l'].value == 1.5 + pfit['cen_g'].value)
    assert (pfit['amp_l'].value == pfit['amp_tot'].value - pfit['amp_g'].value)
    assert (pfit['wid_l'].value == 2 * pfit['wid_g'].value)
def test_constraints2():
    """add a user-defined function to symbol table"""
    def residual(pars, x, sigma=None, data=None):
        yg = gaussian(x, pars['amp_g'].value,
                      pars['cen_g'].value, pars['wid_g'].value)
        yl = lorentzian(x, pars['amp_l'].value,
                   pars['cen_l'].value, pars['wid_l'].value)

        slope = pars['line_slope'].value
        offset = pars['line_off'].value
        model =  yg +  yl + offset + x * slope
        if data is None:
            return model
        if sigma is None:
            return (model - data)
        return (model - data)/sigma


    n = 601
    xmin = 0.
    xmax = 20.0
    x = linspace(xmin, xmax, n)

    data = (gaussian(x, 21, 8.1, 1.2) +
            lorentzian(x, 10, 9.6, 2.4) +
            random.normal(scale=0.23,  size=n) +
            x*0.5)

    pfit = [Parameter(name='amp_g',  value=10),
            Parameter(name='cen_g',  value=9),
            Parameter(name='wid_g',  value=1),

            Parameter(name='amp_tot',  value=20),
            Parameter(name='amp_l',  expr='amp_tot - amp_g'),
            Parameter(name='cen_l',  expr='1.5+cen_g'),
            Parameter(name='line_slope', value=0.0),
            Parameter(name='line_off', value=0.0)]

    sigma = 0.021  # estimate of data error (for all data points)

    myfit = Minimizer(residual, pfit,
                      fcn_args=(x,), fcn_kws={'sigma':sigma, 'data':data},
                      scale_covar=True)

    def width_func(wpar):
        """ """
        return 2*wpar

    myfit.asteval.symtable['wfun'] = width_func
    myfit.params.add(name='wid_l', expr='wfun(wid_g)')

    myfit.leastsq()

    print(' Nfev = ', myfit.nfev)
    print( myfit.chisqr, myfit.redchi, myfit.nfree)

    report_fit(myfit.params)
    pfit= myfit.params
    fit = residual(myfit.params, x)
    assert(pfit['cen_l'].value == 1.5 + pfit['cen_g'].value)
    assert(pfit['amp_l'].value == pfit['amp_tot'].value - pfit['amp_g'].value)
    assert(pfit['wid_l'].value == 2 * pfit['wid_g'].value)
Example #11
0
    def test_sum_of_two_gaussians(self):

        # two user-defined gaussians
        model1 = self.model
        f2 = lambda x, height_, center_, sigma_: gaussian(
            x, height_, center_, sigma_)
        model2 = Model(f2, ['x'])
        values1 = self.true_values()
        values2 = self.true_values()
        values2['sigma'] = 1.5
        values2['height'] = 4
        data = gaussian(x=self.x, **values1)
        data += gaussian(x=self.x, **values2)
        model = self.model + model2
        values2 = {k + '_': v for k, v in values2.items()}
        guess = {
            'sigma': Parameter(value=2, min=0),
            'center': 1,
            'height': 1,
            'sigma_': Parameter(value=1, min=0),
            'center_': 1,
            'height_': 1
        }

        true_values = dict(list(values1.items()) + list(values2.items()))
        result = model.fit(data, x=self.x, **guess)
        assert_results_close(result.values, true_values)

        # user-defined models with common parameter names
        # cannot be added, and should raise
        f = lambda: model1 + model1
        self.assertRaises(NameError, f)

        # two predefined_gaussians, using suffix to differentiate
        model1 = specified_models.Gaussian(['x'])
        model2 = specified_models.Gaussian(['x'], suffix='_')
        model = model1 + model2
        true_values = {
            'center': values1['center'],
            'height': values1['height'],
            'sigma': values1['sigma'],
            'center_': values2['center_'],
            'height_': values2['height_'],
            'sigma_': values2['sigma_']
        }
        guess = {
            'sigma': 2,
            'center': 1,
            'height': 1,
            'sigma_': 1,
            'center_': 1,
            'height_': 1
        }
        result = model.fit(data, x=self.x, **guess)
        assert_results_close(result.values, true_values)

        # without suffix, the names collide and Model should raise
        model1 = specified_models.Gaussian(['x'])
        model2 = specified_models.Gaussian(['x'])
        f = lambda: model1 + model2
        self.assertRaises(NameError, f)
def test_constraints(with_plot=True):
    with_plot = with_plot and HASPYLAB

    def residual(pars, x, sigma=None, data=None):
        yg = gaussian(x, pars['amp_g'].value,
                   pars['cen_g'].value, pars['wid_g'].value)
        yl = loren(x, pars['amp_l'].value,
                   pars['cen_l'].value, pars['wid_l'].value)

        slope = pars['line_slope'].value
        offset = pars['line_off'].value
        model =  yg +  yl + offset + x * slope
        if data is None:
            return model
        if sigma is None:
            return (model - data)
        return (model - data) / sigma


    n = 201
    xmin = 0.
    xmax = 20.0
    x = linspace(xmin, xmax, n)

    data = (gaussian(x, 21, 8.1, 1.2) +
            loren(x, 10, 9.6, 2.4) +
            random.normal(scale=0.23,  size=n) +
            x*0.5)

    if with_plot:
        pylab.plot(x, data, 'r+')

    pfit = [Parameter(name='amp_g',  value=10),
            Parameter(name='cen_g',  value=9),
            Parameter(name='wid_g',  value=1),

            Parameter(name='amp_tot',  value=20),
            Parameter(name='amp_l',  expr='amp_tot - amp_g'),
            Parameter(name='cen_l',  expr='1.5+cen_g'),
            Parameter(name='wid_l',  expr='2*wid_g'),

            Parameter(name='line_slope', value=0.0),
            Parameter(name='line_off', value=0.0)]

    sigma = 0.021  # estimate of data error (for all data points)

    myfit = Minimizer(residual, pfit,
                      fcn_args=(x,), fcn_kws={'sigma':sigma, 'data':data},
                      scale_covar=True)

    myfit.prepare_fit()
    init = residual(myfit.params, x)

    myfit.leastsq()

    print(' Nfev = ', myfit.nfev)
    print( myfit.chisqr, myfit.redchi, myfit.nfree)

    report_fit(myfit.params, min_correl=0.3)

    fit = residual(myfit.params, x)
    if with_plot:
        pylab.plot(x, fit, 'b-')
    assert(myfit.params['cen_l'].value == 1.5 + myfit.params['cen_g'].value)
    assert(myfit.params['amp_l'].value == myfit.params['amp_tot'].value - myfit.params['amp_g'].value)
    assert(myfit.params['wid_l'].value == 2 * myfit.params['wid_g'].value)

    # now, change fit slightly and re-run
    myfit.params['wid_l'].expr = '1.25*wid_g'
    myfit.leastsq()
    report_fit(myfit.params, min_correl=0.4)
    fit2 = residual(myfit.params, x)
    if with_plot:
        pylab.plot(x, fit2, 'k')
        pylab.show()

    assert(myfit.params['cen_l'].value == 1.5 + myfit.params['cen_g'].value)
    assert(myfit.params['amp_l'].value == myfit.params['amp_tot'].value - myfit.params['amp_g'].value)
    assert(myfit.params['wid_l'].value == 1.25 * myfit.params['wid_g'].value)
Example #13
0
 def flexible_func(x, amplitude, center, sigma, **kwargs):
     return gaussian(x, amplitude, center, sigma)
Example #14
0
 def flexible_func(x, height, center, sigma, **kwargs):
     return gaussian(x, height, center, sigma)
Example #15
0
 def flexible_func(x, height, center, sigma, **kwargs):
     return gaussian(x, height, center, sigma)
    slope = pars['line_slope'].value
    offset = pars['line_off'].value
    model =  yg +  yl + offset + x * slope
    if data is None:
        return model
    if sigma is  None:
        return (model - data)
    return (model - data)/sigma


n = 601
xmin = 0.
xmax = 20.0
x = linspace(xmin, xmax, n)

data = (gaussian(x, 21, 8.1, 1.2) +
        lorentzian(x, 10, 9.6, 2.4) +
        random.normal(scale=0.23,  size=n) +
        x*0.5)


if HASPYLAB:
    pylab.plot(x, data, 'r+')

pfit = [Parameter(name='amp_g',  value=10),
        Parameter(name='cen_g',  value=9),
        Parameter(name='wid_g',  value=1),

        Parameter(name='amp_tot',  value=20),
        Parameter(name='amp_l',  expr='amp_tot - amp_g'),
        Parameter(name='cen_l',  expr='1.5+cen_g'),
Example #17
0
 def func(**kwargs):
     height = kwargs[p['height']]
     center = kwargs[p['center']]
     sigma = kwargs[p['sigma']]
     var = kwargs[var_name]
     return gaussian(var, height, center, sigma)