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)

../_images/deerlab-dd_rice-1.png