ExponentialCutoffPowerLaw1D

class astropy.modeling.powerlaws.ExponentialCutoffPowerLaw1D(amplitude=1, x_0=1, alpha=1, x_cutoff=1, **kwargs)[source] [edit on github]

Bases: astropy.modeling.Fittable1DModel

One dimensional power law model with an exponential cutoff.

Parameters:

amplitude : float

Model amplitude

x_0 : float

Reference point

alpha : float

Power law index

x_cutoff : float

Cutoff point

Notes

Model formula (with \(A\) for amplitude and \(\alpha\) for alpha):

\[f(x) = A (x / x_0) ^ {-\alpha} \exp (-x / x_{cutoff})\]

Attributes Summary

alpha
amplitude
param_names
x_0
x_cutoff

Methods Summary

evaluate(x, amplitude, x_0, alpha, x_cutoff) One dimensional exponential cutoff power law model function
fit_deriv(x, amplitude, x_0, alpha, x_cutoff) One dimensional exponential cutoff power law derivative with respect to parameters

Attributes Documentation

alpha
amplitude
param_names = ('amplitude', 'x_0', 'alpha', 'x_cutoff')
x_0
x_cutoff

Methods Documentation

static evaluate(x, amplitude, x_0, alpha, x_cutoff)[source] [edit on github]

One dimensional exponential cutoff power law model function

static fit_deriv(x, amplitude, x_0, alpha, x_cutoff)[source] [edit on github]

One dimensional exponential cutoff power law derivative with respect to parameters