synthpop.modules.initial_mass_function.piecewise_powerlaw

Initial mass function for a piecewise power law, e.g.:

For M ≤ m1: ξ(M) ∝ M^-a0

For m1 < M ≤ m2: ξ(M) ∝ M^-a1

For m2 < M: ξ(M) ∝ M^-a2

The number of splitpoints is modifiable.

Classes

PiecewisePowerlaw

Initial mass function generator for a piecewise power law

Module Contents

class synthpop.modules.initial_mass_function.piecewise_powerlaw.PiecewisePowerlaw(min_mass=None, max_mass=None, alphas: tuple[float] = 1, splitpoints: tuple[float] = (), **kwargs)

Bases: synthpop.modules.initial_mass_function._initial_mass_function.InitialMassFunction

Initial mass function generator for a piecewise power law

Attributes:

min_massfloat

lower initial mass limit

max_massfloat

upper initial mass limit

alphasndarray [float]

power law indices for the mass chunks from lower mass to higher

splitpointsndarray [float]

mass values where pieces split; length must be length alphas minus 1

imf_name = 'Piecewise Powerlaw'

alphas = 1

splitpoints = ()

get_functions(alphas, splitpoints)

get_imf_parts(m_upper, m_lower, a, alpha)

get_F_parts(m_upper, m_lower, a, alpha) → Callable

get_F_inv_parts(m_upper, m_lower, p_upper, p_lower, a, alpha)

imf(m_in)

Initial mass function

Parameters

m_in: initial mass

Returns

prob: probability at the initial mass

F_imf(m_in)

Integral of the initial mass function from 0 to m_in

Parameters

m_in: initial mass

Returns

F: integral

F_imf_inverse(p_in)

Inverse of F_imf

Parameters

p_in : cumulative likelihood

Returns

met

grid_max = 10000

grid_min = 0