Extrapolation: Porod Law

Extrapolate as: I(q) = B + Cp / q^4

class jldesmear.api.extrap_Porod.Extrapolation

I(q) = B + Cp / q^4

calc(q)

Parameters:q (float) – magnitude of scattering vector Returns:value of extrapolation function at q Return type:float

fit_add(reg, x, y, z)

Add a data point to the statistics registers. Called from fit_loop().

Note:

might override in subclass

Parameters:

• reg (obj) – statistics registers (created in fit()), instance of StatsRegClass
• x (float) – independent axis
• y (float) – dependent axis
• z (float) – estimated uncertainty of y

fit_result(reg)

Determine the results of the fit and store them as the set of coefficients in the self.coefficients dictionary. Called from fit().

Note:must override in subclass otherwise fit_result() will throw an exception Parameters:reg (obj) – statistics registers (created in fit()), instance of StatsRegClass