dd_sphere

Particles distributed on a sphere

Syntax

info = dd_sphere()
P = dd_sphere(r,param)
Parameters
  • r - Distance axis (N-array)
  • param - Model parameters
Returns
  • P - Distance distribution (N-array)
  • info - Model information (struct)

Model

../_images/model_scheme_dd_sphere.png

P(r) = \begin{cases} \frac{3r^5}{16R^6} - \frac{9r^3}{4R^4} + \frac{3r^2}{R^3} \quad \text{for} \quad 0 \leq r < 2R \\ 0 \quad \text{for} \quad \text{otherwise} \end{cases}

Variable Symbol Default Lower Upper Description
param(1) R 2.5 0.1 20 Sphere radius

Example using default parameters:

../_images/model_dd_sphere.png

Description

info = dd_sphere()

Returns an info structure containing the specifics of the model:

  • info.model - Full name of the parametric model.
  • info.nparam - Total number of adjustable parameters.
  • info.parameters - Structure array with information on individual parameters.
P = dd_sphere(r,param)

Computes the distance distribution model P from the axis r according to the parameters array param. The required parameters can also be found in the info structure.

References

[1] D.R. Kattnig, D. Hinderberger, Journal of Magnetic Resonance, 230 (2013), 50-63. DOI: 10.1016/j.jmr.2013.01.007