popsynth.distributions package

Submodules

popsynth.distributions.bpl_distribution module

class popsynth.distributions.bpl_distribution.BPLDistribution(seed: int = 1234, name: str = 'bpl')

Bases: LuminosityDistribution

Lmin

alpha

Lbreak

beta

Lmax

__init__(seed: int = 1234, name: str = 'bpl')

A broken power law luminosity distribution.

L ~ L^``alpha`` for L <= Lbreak L ~ L^``beta`` for L > Lbreak

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• Lmin (DistributionParameter) – Minimum value of the luminosity

• alpha (DistributionParameter) – Index of the lower power law

• Lbreak (DistributionParameter) – Luminosity of the power law break

• beta (DistributionParameter) – Index of the upper power law

• Lmax (DistributionParameter) – Maximum value of the luminosity

phi(L)

The functional form of the distribution. not required for sampling :param luminosity: Luminosity

draw_luminosity(size=1)

function to draw the luminosity via an alternative method must be implemented in child class

Parameters

size –

Returns

popsynth.distributions.bpl_distribution.integrate_pl(x0, x1, x2, a1, a2)

Integrate a broken power law between bounds.

Parameters

• x0 – Lower bound

• x1 – Break point

• x2 – Upper bound

• a1 – Lower power law index

• a2 – Upper power low index

popsynth.distributions.bpl_distribution.bpl(x, x0, x1, x2, a1, a2)

Broken power law between bounds.

Parameters

• x – The domain of the function

• x0 – Lower bound

• x1 – Break point

• x2 – Upper bound

• a1 – Lower power law index

• a2 – Upper power low index

popsynth.distributions.bpl_distribution.sample_bpl(u, x0, x1, x2, a1, a2)

Sample from a broken power law between bounds.

Parameters

• u – Uniform random number on {0,1}

• x0 – Lower bound

• x1 – Break point

• x2 – Upper bound

• a1 – Lower power law index

• a2 – Upper power low index

popsynth.distributions.cosmological_distribution module

class popsynth.distributions.cosmological_distribution.CosmologicalDistribution(seed: int = 1234, name: str = 'cosmo', form: Optional[str] = None, truth: Dict[str, Any] = {}, is_rate: bool = True)

Bases: SpatialDistribution

__init__(seed: int = 1234, name: str = 'cosmo', form: Optional[str] = None, truth: Dict[str, Any] = {}, is_rate: bool = True)

Base class for cosmological spatial distributions.

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• form (str) – Mathematical description of distribution

• truth (dict[str, Any]) – True values of parameters

• is_rate (bool) – True if modelling a population of transient events, False if modelling a population of steady-state objects. Affects the time_adjustment method used in cosmo calculations. Default is True.

differential_volume(z)

Differential comoving volume in Gpc^3 sr^-1.

dV/dzdOmega

Parameters

z – Redshift

Returns

The differential comoving volume in Gpc^-3 sr^-1.

transform(L, z)

Transformation from luminosity to energy flux.

L / 4 pi dL^2

dL is in cm. Therefore for L in erg s^-1 returns flux in erg cm^-2 s^-1.

Parameters

• L – Luminosity

• z – Redshift

Returns

Flux

time_adjustment(z)

Time adjustment factor to handle both transient and steady-state populations.

Parameters

z – Redshift

Returns

Appropriate factor depending on is_rate

class popsynth.distributions.cosmological_distribution.SFRDistribution(seed: int = 1234, name: str = 'sfr', is_rate: bool = True)

Bases: CosmologicalDistribution

r0

a

rise

decay

peak

__init__(seed: int = 1234, name: str = 'sfr', is_rate: bool = True)

A star-formation like distribution of the form presented in Cole et al. 2001.

r0``(``a``+``rise``z)/(1 + (z/``peak)^``decay``)

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• is_rate (bool) – True if modelling a population of transient events, False if modelling a population of steady-state objects. Affects the time_adjustment method used in cosmo calculations. Default is True.

• r0 (DistributionParameter) – The local density in units of Gpc^-3

• a (DistributionParameter) – Offset at z=0

• rise (DistributionParameter) – Rise at low z

• decay (DistributionParameter) – Decay at high z

• peak (DistributionParameter) – Peak of z distribution

dNdV(z)

The differential number of objects per volume element

Parameters

distance –

Returns

class popsynth.distributions.cosmological_distribution.ZPowerCosmoDistribution(seed: int = 1234, name: str = 'zpow_cosmo', is_rate: bool = True)

Bases: CosmologicalDistribution

Lambda

delta

__init__(seed: int = 1234, name: str = 'zpow_cosmo', is_rate: bool = True)

A cosmological distribution where the density evolves as a power law.

Lambda (1+z)^``delta``

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• is_rate (bool) – True if modelling a population of transient events, False if modelling a population of steady-state objects. Affects the time_adjustment method used in cosmo calculations. Default is True.

• Lambda (DistributionParameter) – The local density in units of Gpc^-3

• delta (DistributionParameter) – The index of the power law

dNdV(distance)

The differential number of objects per volume element

Parameters

distance –

Returns

popsynth.distributions.delta_distribution module

class popsynth.distributions.delta_distribution.DeltaDistribution(seed: int = 1234, name: str = 'delta')

Bases: LuminosityDistribution

Lp

__init__(seed: int = 1234, name: str = 'delta')

A delta function luminosity distribution, centred on Lp.

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• Lp (DistributionParameter) – The central value

phi(L)

The functional form of the distribution. not required for sampling :param luminosity: Luminosity

draw_luminosity(size=1)

function to draw the luminosity via an alternative method must be implemented in child class

Parameters

size –

Returns

popsynth.distributions.flatland_distribution module

class popsynth.distributions.flatland_distribution.FlatlandDistribution(seed: int = 1234, name: str = 'flatland', form: Optional[str] = None)

Bases: SpatialDistribution

Lambda

__init__(seed: int = 1234, name: str = 'flatland', form: Optional[str] = None)

A flat spatial distribution with only length.

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• form (str) – Mathematical description of distribution

• Lambda (DistributionParameter) – Length

differential_volume(r)

The differential volume

Parameters

distance – Distance

transform(L, r)

The transform from luminosity to flux for the

Parameters

• flux –

• distance –

Returns

dNdV(distance)

The differential number of objects per volume element

Parameters

distance –

Returns

popsynth.distributions.log10_normal_distribution module

class popsynth.distributions.log10_normal_distribution.Log10NormalDistribution(seed: int = 1234, name: str = 'log10norm')

Bases: LuminosityDistribution

mu

tau

__init__(seed: int = 1234, name: str = 'log10norm')

A log10-normal luminosity function

Log10Normal(mu, tau)

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• mu (DistributionParameter) – Mean of the log10 normal

• tau (DistributionParameter) – Standard deviation of the log10 normal

phi(L)

The functional form of the distribution. not required for sampling :param luminosity: Luminosity

draw_luminosity(size=1)

function to draw the luminosity via an alternative method must be implemented in child class

Parameters

size –

Returns

popsynth.distributions.log_normal_distribution module

class popsynth.distributions.log_normal_distribution.LogNormalDistribution(seed: int = 1234, name: str = 'lognorm')

Bases: LuminosityDistribution

mu

tau

__init__(seed: int = 1234, name: str = 'lognorm')

A log-normal luminosity distribution.

LogNormal(mu, tau)

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• mu (DistributionParameter) – Mean of the log normal

• tau (DistributionParameter) – Standard deviation of the log normal

phi(L)

The functional form of the distribution. not required for sampling :param luminosity: Luminosity

draw_luminosity(size=1)

function to draw the luminosity via an alternative method must be implemented in child class

Parameters

size –

Returns

popsynth.distributions.pareto_distribution module

class popsynth.distributions.pareto_distribution.ParetoDistribution(seed: int = 1234, name: str = 'pareto')

Bases: LuminosityDistribution

Lmin

alpha

__init__(seed: int = 1234, name: str = 'pareto')

A Pareto luminosity function.

alpha``*``Lmin``^``alpha / L^(``alpha``+1)

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• Lmin (DistributionParameter) – Minimum value of the luminosity

• alpha (DistributionParameter) – Index of the pareto distribution

phi(L)

The functional form of the distribution. not required for sampling :param luminosity: Luminosity

draw_luminosity(size: int = 1)

function to draw the luminosity via an alternative method must be implemented in child class

Parameters

size –

Returns

popsynth.distributions.schechter_distribution module

class popsynth.distributions.schechter_distribution.SchechterDistribution(seed: int = 1234, name: str = 'schechter')

Bases: LuminosityDistribution

Lmin

alpha

__init__(seed: int = 1234, name: str = 'schechter')

A Schechter luminosity function as in Schechter, Astrophysical Journal, Vol. 203, p. 297-306 (1976).

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• Lmin (DistributionParameter) – Minimum value of the luminosity

• alpha (DistributionParameter) – Index of the distribution

phi(L)

The functional form of the distribution. not required for sampling :param luminosity: Luminosity

draw_luminosity(size=1)

function to draw the luminosity via an alternative method must be implemented in child class

Parameters

size –

Returns

popsynth.distributions.spherical_distribution module

class popsynth.distributions.spherical_distribution.SphericalDistribution(seed: int = 1234, name: str = 'sphere', form: Optional[str] = None)

Bases: SpatialDistribution

__init__(seed: int = 1234, name: str = 'sphere', form: Optional[str] = None)

A generic spherical distribution. Can be inherited to form more complex spherical distributions

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• form (str) – Mathematical description of distribution

differential_volume(r)

The differential volume

Parameters

distance – Distance

transform(L, r)

The transform from luminosity to flux for the

Parameters

• flux –

• distance –

Returns

class popsynth.distributions.spherical_distribution.ConstantSphericalDistribution(seed: int = 1234, name: str = 'cons_sphere', form: Optional[str] = None)

Bases: SphericalDistribution

Lambda

__init__(seed: int = 1234, name: str = 'cons_sphere', form: Optional[str] = None)

A spherical distribution with constant density.

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• form (str) – Mathematical description of distribution

• Lambda (DistributionParameter) – Density per unit volume

dNdV(distance)

The differential number of objects per volume element

Parameters

distance –

Returns

class popsynth.distributions.spherical_distribution.ZPowerSphericalDistribution(seed: int = 1234, name: str = 'zpow_sphere')

Bases: ConstantSphericalDistribution

delta

__init__(seed: int = 1234, name: str = 'zpow_sphere')

A spherical distribution with a power law density profile.

Lambda (1+r)^``delta``

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• form (str) – Mathematical description of distribution

• delta (DistributionParameter) – Index of power law distribution

dNdV(distance)

The differential number of objects per volume element

Parameters

distance –

Returns

popsynth.distributions.spiral_galaxy_distribution module

class popsynth.distributions.spiral_galaxy_distribution.SpiralGalaxyDistribution(seed: int = 1234, name: str = 'spiral_galaxy', form: Optional[str] = None)

Bases: SphericalDistribution

rho

a

b

R1

R0

__init__(seed: int = 1234, name: str = 'spiral_galaxy', form: Optional[str] = None)

A spiral galaxy spatial distribution.

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• form (str) – Mathematical description of distribution

• rho (DistributionParameter) – Local density

• a (DistributionParameter) – Shape parameter

• b (DistributionParameter) – Shape parameter

• R1 (DistributionParameter) – Scale parameter

• R0 (DistributionParameter) – Scale parameter

dNdV(r)

The differential number of objects per volume element

Parameters

distance –

Returns

draw_sky_positions(size)

Based on Wainscoat 1992 and Faucher-Giguere 2007.

Code thanks to Mortiz Pleintinger.

popsynth.distributions.uniform_distribution module

class popsynth.distributions.uniform_distribution.LogUniLuminiosityDistribution(seed: int = 1234, name: str = 'logunilum')

Bases: LuminosityDistribution

Lmin

Lmax

__init__(seed: int = 1234, name: str = 'logunilum')

A broken power law luminosity distribution.

L ~ L^``alpha`` for L <= Lbreak L ~ L^``beta`` for L > Lbreak

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• Lmin (DistributionParameter) – Minimum value of the luminosity

• Lmax (DistributionParameter) – Maximum value of the luminosity

phi(L)

The functional form of the distribution. not required for sampling :param luminosity: Luminosity

draw_luminosity(size=1)

function to draw the luminosity via an alternative method must be implemented in child class

Parameters

size –

Returns

class popsynth.distributions.uniform_distribution.UniformCosmoDistribution(seed: int = 1234, name: str = 'uniform_cosmo', is_rate: bool = True)

Bases: CosmologicalDistribution

r0

zmin

zmax

__init__(seed: int = 1234, name: str = 'uniform_cosmo', is_rate: bool = True)

A cosmological distribution where the density evolves uniformly.

Lambda (1+z)^``delta``

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• is_rate (bool) – True if modelling a population of transient events, False if modelling a population of steady-state objects. Affects the time_adjustment method used in cosmo calculations. Default is True.

• Lambda (DistributionParameter) – The local density in units of Gpc^-3

• delta (DistributionParameter) – The index of the power law

dNdV(distance)

The differential number of objects per volume element

Parameters

distance –

Returns

Module contents

class popsynth.distributions.SphericalDistribution(seed: int = 1234, name: str = 'sphere', form: Optional[str] = None)

Bases: SpatialDistribution

__init__(seed: int = 1234, name: str = 'sphere', form: Optional[str] = None)

A generic spherical distribution. Can be inherited to form more complex spherical distributions

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• form (str) – Mathematical description of distribution

differential_volume(r)

The differential volume

Parameters

distance – Distance

transform(L, r)

The transform from luminosity to flux for the

Parameters

• flux –

• distance –

Returns

class popsynth.distributions.CosmologicalDistribution(seed: int = 1234, name: str = 'cosmo', form: Optional[str] = None, truth: Dict[str, Any] = {}, is_rate: bool = True)

Bases: SpatialDistribution

__init__(seed: int = 1234, name: str = 'cosmo', form: Optional[str] = None, truth: Dict[str, Any] = {}, is_rate: bool = True)

Base class for cosmological spatial distributions.

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• form (str) – Mathematical description of distribution

• truth (dict[str, Any]) – True values of parameters

• is_rate (bool) – True if modelling a population of transient events, False if modelling a population of steady-state objects. Affects the time_adjustment method used in cosmo calculations. Default is True.

differential_volume(z)

Differential comoving volume in Gpc^3 sr^-1.

dV/dzdOmega

Parameters

z – Redshift

Returns

The differential comoving volume in Gpc^-3 sr^-1.

transform(L, z)

Transformation from luminosity to energy flux.

L / 4 pi dL^2

dL is in cm. Therefore for L in erg s^-1 returns flux in erg cm^-2 s^-1.

Parameters

• L – Luminosity

• z – Redshift

Returns

Flux

time_adjustment(z)

Time adjustment factor to handle both transient and steady-state populations.

Parameters

z – Redshift

Returns

Appropriate factor depending on is_rate

class popsynth.distributions.SFRDistribution(seed: int = 1234, name: str = 'sfr', is_rate: bool = True)

Bases: CosmologicalDistribution

r0

a

rise

decay

peak

__init__(seed: int = 1234, name: str = 'sfr', is_rate: bool = True)

A star-formation like distribution of the form presented in Cole et al. 2001.

r0``(``a``+``rise``z)/(1 + (z/``peak)^``decay``)

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• is_rate (bool) – True if modelling a population of transient events, False if modelling a population of steady-state objects. Affects the time_adjustment method used in cosmo calculations. Default is True.

• r0 (DistributionParameter) – The local density in units of Gpc^-3

• a (DistributionParameter) – Offset at z=0

• rise (DistributionParameter) – Rise at low z

• decay (DistributionParameter) – Decay at high z

• peak (DistributionParameter) – Peak of z distribution

dNdV(z)

The differential number of objects per volume element

Parameters

distance –

Returns

class popsynth.distributions.ZPowerCosmoDistribution(seed: int = 1234, name: str = 'zpow_cosmo', is_rate: bool = True)

Bases: CosmologicalDistribution

Lambda

delta

__init__(seed: int = 1234, name: str = 'zpow_cosmo', is_rate: bool = True)

A cosmological distribution where the density evolves as a power law.

Lambda (1+z)^``delta``

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• is_rate (bool) – True if modelling a population of transient events, False if modelling a population of steady-state objects. Affects the time_adjustment method used in cosmo calculations. Default is True.

• Lambda (DistributionParameter) – The local density in units of Gpc^-3

• delta (DistributionParameter) – The index of the power law

dNdV(distance)

The differential number of objects per volume element

Parameters

distance –

Returns

class popsynth.distributions.ParetoDistribution(seed: int = 1234, name: str = 'pareto')

Bases: LuminosityDistribution

Lmin

alpha

__init__(seed: int = 1234, name: str = 'pareto')

A Pareto luminosity function.

alpha``*``Lmin``^``alpha / L^(``alpha``+1)

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• Lmin (DistributionParameter) – Minimum value of the luminosity

• alpha (DistributionParameter) – Index of the pareto distribution

phi(L)

The functional form of the distribution. not required for sampling :param luminosity: Luminosity

draw_luminosity(size: int = 1)

function to draw the luminosity via an alternative method must be implemented in child class

Parameters

size –

Returns

class popsynth.distributions.Log10NormalDistribution(seed: int = 1234, name: str = 'log10norm')

Bases: LuminosityDistribution

mu

tau

__init__(seed: int = 1234, name: str = 'log10norm')

A log10-normal luminosity function

Log10Normal(mu, tau)

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• mu (DistributionParameter) – Mean of the log10 normal

• tau (DistributionParameter) – Standard deviation of the log10 normal

phi(L)

The functional form of the distribution. not required for sampling :param luminosity: Luminosity

draw_luminosity(size=1)

function to draw the luminosity via an alternative method must be implemented in child class

Parameters

size –

Returns

class popsynth.distributions.LogNormalDistribution(seed: int = 1234, name: str = 'lognorm')

Bases: LuminosityDistribution

mu

tau

__init__(seed: int = 1234, name: str = 'lognorm')

A log-normal luminosity distribution.

LogNormal(mu, tau)

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• mu (DistributionParameter) – Mean of the log normal

• tau (DistributionParameter) – Standard deviation of the log normal

phi(L)

The functional form of the distribution. not required for sampling :param luminosity: Luminosity

draw_luminosity(size=1)

function to draw the luminosity via an alternative method must be implemented in child class

Parameters

size –

Returns

class popsynth.distributions.SchechterDistribution(seed: int = 1234, name: str = 'schechter')

Bases: LuminosityDistribution

Lmin

alpha

__init__(seed: int = 1234, name: str = 'schechter')

A Schechter luminosity function as in Schechter, Astrophysical Journal, Vol. 203, p. 297-306 (1976).

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• Lmin (DistributionParameter) – Minimum value of the luminosity

• alpha (DistributionParameter) – Index of the distribution

phi(L)

The functional form of the distribution. not required for sampling :param luminosity: Luminosity

draw_luminosity(size=1)

function to draw the luminosity via an alternative method must be implemented in child class

Parameters

size –

Returns

class popsynth.distributions.BPLDistribution(seed: int = 1234, name: str = 'bpl')

Bases: LuminosityDistribution

Lmin

alpha

Lbreak

beta

Lmax

__init__(seed: int = 1234, name: str = 'bpl')

A broken power law luminosity distribution.

L ~ L^``alpha`` for L <= Lbreak L ~ L^``beta`` for L > Lbreak

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• Lmin (DistributionParameter) – Minimum value of the luminosity

• alpha (DistributionParameter) – Index of the lower power law

• Lbreak (DistributionParameter) – Luminosity of the power law break

• beta (DistributionParameter) – Index of the upper power law

• Lmax (DistributionParameter) – Maximum value of the luminosity

phi(L)

The functional form of the distribution. not required for sampling :param luminosity: Luminosity

draw_luminosity(size=1)

function to draw the luminosity via an alternative method must be implemented in child class

Parameters

size –

Returns

class popsynth.distributions.ConstantSphericalDistribution(seed: int = 1234, name: str = 'cons_sphere', form: Optional[str] = None)

Bases: SphericalDistribution

Lambda

__init__(seed: int = 1234, name: str = 'cons_sphere', form: Optional[str] = None)

A spherical distribution with constant density.

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• form (str) – Mathematical description of distribution

• Lambda (DistributionParameter) – Density per unit volume

dNdV(distance)

The differential number of objects per volume element

Parameters

distance –

Returns

class popsynth.distributions.ZPowerSphericalDistribution(seed: int = 1234, name: str = 'zpow_sphere')

Bases: ConstantSphericalDistribution

delta

__init__(seed: int = 1234, name: str = 'zpow_sphere')

A spherical distribution with a power law density profile.

Lambda (1+r)^``delta``

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• form (str) – Mathematical description of distribution

• delta (DistributionParameter) – Index of power law distribution

dNdV(distance)

The differential number of objects per volume element

Parameters

distance –

Returns

class popsynth.distributions.DeltaDistribution(seed: int = 1234, name: str = 'delta')

Bases: LuminosityDistribution

Lp

__init__(seed: int = 1234, name: str = 'delta')

A delta function luminosity distribution, centred on Lp.

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• Lp (DistributionParameter) – The central value

phi(L)

The functional form of the distribution. not required for sampling :param luminosity: Luminosity

draw_luminosity(size=1)

function to draw the luminosity via an alternative method must be implemented in child class

Parameters

size –

Returns

class popsynth.distributions.FlatlandDistribution(seed: int = 1234, name: str = 'flatland', form: Optional[str] = None)

Bases: SpatialDistribution

Lambda

__init__(seed: int = 1234, name: str = 'flatland', form: Optional[str] = None)

A flat spatial distribution with only length.

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• form (str) – Mathematical description of distribution

• Lambda (DistributionParameter) – Length

differential_volume(r)

The differential volume

Parameters

distance – Distance

transform(L, r)

The transform from luminosity to flux for the

Parameters

• flux –

• distance –

Returns

dNdV(distance)

The differential number of objects per volume element

Parameters

distance –

Returns

class popsynth.distributions.SpiralGalaxyDistribution(seed: int = 1234, name: str = 'spiral_galaxy', form: Optional[str] = None)

Bases: SphericalDistribution

rho

a

b

R1

R0

__init__(seed: int = 1234, name: str = 'spiral_galaxy', form: Optional[str] = None)

A spiral galaxy spatial distribution.

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• form (str) – Mathematical description of distribution

• rho (DistributionParameter) – Local density

• a (DistributionParameter) – Shape parameter

• b (DistributionParameter) – Shape parameter

• R1 (DistributionParameter) – Scale parameter

• R0 (DistributionParameter) – Scale parameter

dNdV(r)

The differential number of objects per volume element

Parameters

distance –

Returns

draw_sky_positions(size)

Based on Wainscoat 1992 and Faucher-Giguere 2007.

Code thanks to Mortiz Pleintinger.

class popsynth.distributions.LogUniLuminiosityDistribution(seed: int = 1234, name: str = 'logunilum')

Bases: LuminosityDistribution

Lmin

Lmax

__init__(seed: int = 1234, name: str = 'logunilum')

A broken power law luminosity distribution.

L ~ L^``alpha`` for L <= Lbreak L ~ L^``beta`` for L > Lbreak

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• Lmin (DistributionParameter) – Minimum value of the luminosity

• Lmax (DistributionParameter) – Maximum value of the luminosity

phi(L)

The functional form of the distribution. not required for sampling :param luminosity: Luminosity

draw_luminosity(size=1)

function to draw the luminosity via an alternative method must be implemented in child class

Parameters

size –

Returns

class popsynth.distributions.UniformCosmoDistribution(seed: int = 1234, name: str = 'uniform_cosmo', is_rate: bool = True)

Bases: CosmologicalDistribution

r0

zmin

zmax

__init__(seed: int = 1234, name: str = 'uniform_cosmo', is_rate: bool = True)

A cosmological distribution where the density evolves uniformly.

Lambda (1+z)^``delta``

Parameters

• seed (int) – Random seed

• name (str) – Name of the distribution

• is_rate (bool) – True if modelling a population of transient events, False if modelling a population of steady-state objects. Affects the time_adjustment method used in cosmo calculations. Default is True.

• Lambda (DistributionParameter) – The local density in units of Gpc^-3

• delta (DistributionParameter) – The index of the power law

dNdV(distance)

The differential number of objects per volume element

Parameters

distance –

Returns