Source code for camb.dark_energy

from .baseconfig import F2003Class, fortran_class, numpy_1d, CAMBError, np
from ctypes import c_int, c_double, byref, POINTER, c_bool


[docs]class DarkEnergyModel(F2003Class): """ Abstract base class for dark energy model implementations. """ _fields_ = [ ("__is_cosmological_constant", c_bool), ("__num_perturb_equations", c_int)] def validate_params(self): return True
[docs]class DarkEnergyEqnOfState(DarkEnergyModel): """ Abstract base class for models using w and wa parameterization with use w(a) = w + (1-a)*wa parameterization, or call set_w_a_table to set another tabulated w(a). If tabulated w(a) is used, w and wa are set to approximate values at z=0. See :meth:`.model.CAMBparams.set_initial_power_function` for a convenience constructor function to set a general interpolated P(k) model from a python function. """ _fortran_class_module_ = 'DarkEnergyInterface' _fortran_class_name_ = 'TDarkEnergyEqnOfState' _fields_ = [ ("w", c_double, "w(0)"), ("wa", c_double, "-dw/da(0)"), ("cs2", c_double, "fluid rest-frame sound speed squared"), ("use_tabulated_w", c_bool, "using an interpolated tabulated w(a) rather than w, wa above"), ("__no_perturbations", c_bool, "turn off perturbations (unphysical, so hidden in Python)") ] _methods_ = [('SetWTable', [numpy_1d, numpy_1d, POINTER(c_int)])]
[docs] def set_params(self, w=-1.0, wa=0, cs2=1.0): """ Set the parameters so that P(a)/rho(a) = w(a) = w + (1-a)*wa :param w: w(0) :param wa: -dw/da(0) :param cs2: fluid rest-frame sound speed squared """ self.w = w self.wa = wa self.cs2 = cs2 self.validate_params()
[docs] def set_w_a_table(self, a, w): """ Set w(a) from numerical values (used as cublic spline). Note this is quite slow. :param a: array of scale factors :param w: array of w(a) :return: self """ if len(a) != len(w): raise ValueError('Dark energy w(a) table non-equal sized arrays') if not np.isclose(a[-1], 1): raise ValueError('Dark energy w(a) arrays must end at a=1') self.f_SetWTable(a, w, byref(c_int(len(a)))) return self
[docs]@fortran_class class DarkEnergyFluid(DarkEnergyEqnOfState): """ Class implementing the w, wa or splined w(a) parameterization using the constant sound-speed signle fluid model (as for single-field quintessense). """ _fortran_class_module_ = 'DarkEnergyFluid' _fortran_class_name_ = 'TDarkEnergyFluid' def validate_params(self): if not self.use_tabulated_w and self.wa and (self.w < -1 - 1e-6 or 1 + self.w + self.wa < -1 - 1e-6): raise CAMBError('fluid dark energy model does not support w crossing -1')
[docs]@fortran_class class DarkEnergyPPF(DarkEnergyEqnOfState): """ Class implementating the w, wa or splined w(a) parameterization in the PPF perturbation approximation (`arXiv:0808.3125 <https://arxiv.org/abs/0808.3125>`_) Use inherited methods to set parameters or interpolation table. """ # cannot declare c_Gamma_ppf directly here as have not defined all fields in DarkEnergyEqnOfState (TCubicSpline) _fortran_class_module_ = 'DarkEnergyPPF' _fortran_class_name_ = 'TDarkEnergyPPF'
[docs]@fortran_class class AxionEffectiveFluid(DarkEnergyModel): """ Example implementation of a specifc (early) dark energy fluid model (`arXiv:1806.10608 <https://arxiv.org/abs/1806.10608>`_). Not well tested, but should serve to demonstrate how to make your own custom classes. """ _fields_ = [ ("w_n", c_double), ("om", c_double), ("a_c", c_double), ("theta_i", c_double)] _fortran_class_name_ = 'TAxionEffectiveFluid' _fortran_class_module_ = 'DarkEnergyFluid' def set_params(self, w_n, om, a_c): self.w_n = w_n self.om = om self.a_c = a_c
# short names for models that support w/wa F2003Class._class_names.update({'fluid': DarkEnergyFluid, 'ppf': DarkEnergyPPF})