Python numpy.polyval方法代码示例

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import polyval [as 别名]
def fit_cubic(y0, y1, g0, g1):
    """Fit cubic polynomial to function values and derivatives at x = 0, 1.

    Returns position and function value of minimum if fit succeeds. Fit does
    not succeeds if

    1. polynomial doesn't have extrema or
    2. maximum is from (0,1) or
    3. maximum is closer to 0.5 than minimum
    """
    a = 2 * (y0 - y1) + g0 + g1
    b = -3 * (y0 - y1) - 2 * g0 - g1
    p = np.array([a, b, g0, y0])
    r = np.roots(np.polyder(p))
    if not np.isreal(r).all():
        return None, None
    r = sorted(x.real for x in r)
    if p[0] > 0:
        maxim, minim = r
    else:
        minim, maxim = r
    if 0 < maxim < 1 and abs(minim - 0.5) > abs(maxim - 0.5):
        return None, None
    return minim, np.polyval(p, minim) 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import polyval [as 别名]
def calc_phase_delay(coeff, w, w0):
    """
    expression for the phase -- coeff[0] + coeff[1]*(w - w0)/1! + coeff[2]*(w - w0)**2/2! + coeff[3]*(w - w0)**3/3!
    coeff is a list with
    coeff[0] =: measured in [rad]      --- phase
    coeff[1] =: measured in [fm s ^ 1] --- group delay
    coeff[2] =: measured in [fm s ^ 2] --- group delay dispersion (GDD)
    coeff[3] =: measured in [fm s ^ 3] --- third-order dispersion (TOD)
    ...
    """
    delta_w = w - w0
    _logger.debug('calculating phase delay')
    _logger.debug(ind_str + 'coeffs for compression = {}'.format(coeff))
    coeff_norm = [ci / (1e15) ** i / factorial(i) for i, ci in enumerate(coeff)]
    coeff_norm = list(coeff_norm)[::-1]
    _logger.debug(ind_str + 'coeffs_norm = {}'.format(coeff_norm))
    delta_phi = np.polyval(coeff_norm, delta_w)
    _logger.debug(ind_str + 'delta_phi[0] = {}'.format(delta_phi[0]))
    _logger.debug(ind_str + 'delta_phi[-1] = {}'.format(delta_phi[-1]))
    _logger.debug(ind_str + 'done')

    return delta_phi 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import polyval [as 别名]
def get_minimum_energy_path(self, pressure=None):
        """

        Args:
            pressure:

        Returns:

        """
        if pressure is not None:
            raise NotImplemented()
        v_min_lst = []
        for c in self._coeff.T:
            v_min = np.roots(np.polyder(c, 1))
            p_der2 = np.polyder(c, 2)
            p_val2 = np.polyval(p_der2, v_min)
            v_m_lst = v_min[p_val2 > 0]
            if len(v_m_lst) > 0:
                v_min_lst.append(v_m_lst[0])
            else:
                v_min_lst.append(np.nan)
        return np.array(v_min_lst) 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import polyval [as 别名]
def interpolate_volume(self, volumes, fit_order=None):
        """

        Args:
            volumes:
            fit_order:

        Returns:

        """
        if fit_order is not None:
            self._fit_order = fit_order
        new = self.copy()
        new.volumes = volumes
        new.energies = np.array([np.polyval(self._coeff, v) for v in volumes]).T
        return new 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import polyval [as 别名]
def contour_pressure(self):
        """

        Returns:

        """
        try:
            import pylab as plt
        except ImportError:
            import matplotlib.pyplot as plt
        x, y = self.meshgrid()
        p_coeff = np.polyfit(self.volumes, self.pressure.T, deg=self._fit_order)
        p_grid = np.array([np.polyval(p_coeff, v) for v in self._volumes]).T
        plt.contourf(x, y, p_grid)
        plt.plot(self.get_minimum_energy_path(), self.temperatures)
        plt.xlabel("Volume [$\AA^3$]")
        plt.ylabel("Temperature [K]") 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import polyval [as 别名]
def contour_entropy(self):
        """

        Returns:

        """
        try:
            import pylab as plt
        except ImportError:
            import matplotlib.pyplot as plt
        s_coeff = np.polyfit(self.volumes, self.entropy.T, deg=self._fit_order)
        s_grid = np.array([np.polyval(s_coeff, v) for v in self.volumes]).T
        x, y = self.meshgrid()
        plt.contourf(x, y, s_grid)
        plt.plot(self.get_minimum_energy_path(), self.temperatures)
        plt.xlabel("Volume [$\AA^3$]")
        plt.ylabel("Temperature [K]") 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import polyval [as 别名]
def detrend(x, deg=1):
    """
    remove polynomial from data.
    used by autocorr_noise_id()

    Parameters
    ----------
    x: numpy.array
        time-series
    deg: int
        degree of polynomial to remove from x

    Returns
    -------
    x_detrended: numpy.array
        detrended time-series
    """
    t = range(len(x))
    p = np.polyfit(t, x, deg)
    residual = x - np.polyval(p, t)
    return residual

########################################################################
# Equivalent Degrees of Freedom 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import polyval [as 别名]
def test_PVSystem_sapm_effective_irradiance(sapm_module_params, mocker):
    system = pvsystem.PVSystem(module_parameters=sapm_module_params)
    mocker.spy(pvsystem, 'sapm_effective_irradiance')

    poa_direct = 900
    poa_diffuse = 100
    airmass_absolute = 1.5
    aoi = 0
    p = (sapm_module_params['A4'], sapm_module_params['A3'],
         sapm_module_params['A2'], sapm_module_params['A1'],
         sapm_module_params['A0'])
    f1 = np.polyval(p, airmass_absolute)
    expected = f1 * (poa_direct + sapm_module_params['FD'] * poa_diffuse)
    out = system.sapm_effective_irradiance(
        poa_direct, poa_diffuse, airmass_absolute, aoi)
    pvsystem.sapm_effective_irradiance.assert_called_once_with(
        poa_direct, poa_diffuse, airmass_absolute, aoi, sapm_module_params)
    assert_allclose(out, expected, atol=0.1) 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import polyval [as 别名]
def alt_sg_coeffs(window_length, polyorder, pos):
    """This is an alternative implementation of the SG coefficients.

    It uses numpy.polyfit and numpy.polyval.  The results should be
    equivalent to those of savgol_coeffs(), but this implementation
    is slower.

    window_length should be odd.

    """
    if pos is None:
        pos = window_length // 2
    t = np.arange(window_length)
    unit = (t == pos).astype(int)
    h = np.polyval(np.polyfit(t, unit, polyorder), t)
    return h 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import polyval [as 别名]
def test_auto(self):
        # Test dfreqresp() real part calculation.
        # 1st order low-pass filter: H(z) = 1 / (z - 0.2),
        system = TransferFunction(1, [1, -0.2], dt=0.1)
        w = [0.1, 1, 10, 100]
        w, H = dfreqresp(system, w=w)
        jw = np.exp(w * 1j)
        y = np.polyval(system.num, jw) / np.polyval(system.den, jw)

        # test real
        expected_re = y.real
        assert_almost_equal(H.real, expected_re)

        # test imag
        expected_im = y.imag
        assert_almost_equal(H.imag, expected_im) 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import polyval [as 别名]
def _nf(self, type_def, nf_model, nf_fit_coeff, gain_min, gain_flatmax, gain_target):
        # if hybrid raman, use edfa_gain_flatmax attribute, else use gain_flatmax
        #gain_flatmax = getattr(params, 'edfa_gain_flatmax', params.gain_flatmax)
        pad = max(gain_min - gain_target, 0)
        gain_target += pad
        dg = max(gain_flatmax - gain_target, 0)
        if type_def == 'variable_gain':
            g1a = gain_target - nf_model.delta_p - dg
            nf_avg = lin2db(db2lin(nf_model.nf1) + db2lin(nf_model.nf2) / db2lin(g1a))
        elif type_def == 'fixed_gain':
            nf_avg = nf_model.nf0
        elif type_def == 'openroadm':
            pin_ch = self.pin_db - lin2db(self.nch)
            # model OSNR = f(Pin)
            nf_avg = pin_ch - polyval(nf_model.nf_coef, pin_ch) + 58
        elif type_def == 'advanced_model':
            nf_avg = polyval(nf_fit_coeff, -dg)
        else:
            assert False, "Unrecognized amplifier type, this should have been checked by the JSON loader"
        return nf_avg + pad, pad 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import polyval [as 别名]
def _fractal_correlation_plot(r_vals, corr, d2):
    fit = 2 ** np.polyval(d2, np.log2(r_vals))
    plt.loglog(r_vals, corr, "bo")
    plt.loglog(r_vals, fit, "r", label=r"$D2$ = %0.3f" % d2[0])
    plt.title("Correlation Dimension")
    plt.xlabel(r"$\log_{2}$(r)")
    plt.ylabel(r"$\log_{2}$(c)")
    plt.legend()
    plt.show() 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import polyval [as 别名]
def _fractal_dfa_trends(segments, window, order=1):
    x = np.arange(window)

    coefs = np.polyfit(x[:window], segments.T, order).T

    # TODO: Could this be optimized? Something like np.polyval(x[:window], coefs)
    trends = np.array([np.polyval(coefs[j], x) for j in np.arange(len(segments))])

    return trends 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import polyval [as 别名]
def _fractal_dfa_plot(windows, fluctuations, dfa):
    fluctfit = 2 ** np.polyval(dfa, np.log2(windows))
    plt.loglog(windows, fluctuations, "bo")
    plt.loglog(windows, fluctfit, "r", label=r"$\alpha$ = %0.3f" % dfa[0])
    plt.title("DFA")
    plt.xlabel(r"$\log_{2}$(Window)")
    plt.ylabel(r"$\log_{2}$(Fluctuation)")
    plt.legend()
    plt.show()


# =============================================================================
#  Utils MDDFA
# ============================================================================= 

# 需要导入模块: import numpy [as 别名]
# 或者: from numpy import polyval [as 别名]
def _fit_polynomial(y, X, order=2):
    # Generating weights and model for polynomial function with a given degree
    y_predicted = np.polyval(np.polyfit(X, y, order), X)
    return y_predicted