deerlab.dd_rice¶

dd_rice = <deerlab.model.Model object>¶

3D-Rice distribution model

Parameters:

rarray_like: Distance axis, in nanometers.
locationscalar: Location.
spreadscalar: Spread.

Returns:

Pndarray: Distance distribution.

Notes

Parameter List

Name	Lower	Upper	Type	Frozen	Unit	Description
`location`	1	20	nonlin	No	nm	Location
`spread`	0.1	5	nonlin	No	nm	Spread

Model

$P(r) = \frac{\nu^{n/2-1}}{\sigma^2}r^{n/2}\exp\left(-\frac{(r^2+\nu^2)}{2\sigma^2}\right)I_{n/2-1}\left(\frac{r\nu}{\sigma^2} \right)$

where $\nu$ is the location of the distribution, $\sigma$ its spread, $n=3$ , and $I_{n/2-1}(x)$ is the modified Bessel function of the first kind with order $n/2-1$ . This is a three-dimensional non-central chi distribution, the 3D generalization of the 2D Rice distribution.

Examples

Example of the model evaluated at the start values of the parameters:

(Source code, png, hires.png, pdf)