specparam.modes.funcs.double_expo_function

specparam.modes.funcs.double_expo_function(xs, *params)

Double exponential function, for fitting aperiodic component with two exponents and a knee.

Parameters:

xs1d array

Input x-axis values.

*paramsfloat

Parameters that define the the double exponent function: offset, exp0, knee, exp1.

Returns:

ys1d array

Output values for exponential function.

Notes

This is an aperiodic fit function, defined for use with LINEAR freqs and LOG power.

Defines a double-exponent 1/f fit function as:

\[A(F) = 10^b * \frac{1}{F^{\chi_{0}} * (k + F^{\chi_{1}})}\]

Note that the above function form is defined in linear/linear space. The equivalent for linear/log, as implemented in the code, is:

\[A(F) = b - \log(F^{\chi_{0}} * (k + F^{\chi_{1}}))\]