Difference between revisions of "G2fplanck.m"

From Spinach Documentation Wiki
Jump to: navigation, search
(Sync syntax/arguments/outputs with current Spinach source)
(Update function See also links and function index membership)
 
(6 intermediate revisions by the same user not shown)
Line 1: Line 1:
 
{{DISPLAYTITLE:g2fplanck.m}} __NOTOC__
 
{{DISPLAYTITLE:g2fplanck.m}} __NOTOC__
 
+
Returns the magnetic field gradient operators used by the imaging module within the Fokker-Planck formalism; the output cell array contains {Gx,Gy,Gz}, which should be added to the Hamiltonian with appropriate coefficients, and gradients are assumed linear and centred on the middle of the sample.
Returns magnetic field gradient operators within the Fokker-Planck formalism used in the imaging module of ''Spinach''.
 
  
 
==Syntax==
 
==Syntax==
  
G=g2fplanck(spin_system,parameters)
+
    G=g2fplanck(spin_system,parameters)
  
==Arguments==
+
==Parameters==
  
parameters.dims    - a vector with one, two or three  
+
  parameters.dims    - a vector with one, two or three  
 
                         elements giving the dimensions
 
                         elements giving the dimensions
 
                         of the box, metres
 
                         of the box, metres
Line 19: Line 18:
 
==Outputs==
 
==Outputs==
  
G - a cell array with the three gradient operators
+
  G - a cell array with the three gradient operators  
 
       ordered as {Gx,Gy,Gz}, normalised to 1 T/m, empty
 
       ordered as {Gx,Gy,Gz}, normalised to 1 T/m, empty
 
       matrices for non-exitent dimensions
 
       matrices for non-exitent dimensions
 
Note: gradients are assumed to be linear and centered on the
 
      middle of the sample.
 
 
Note: the direct product order is Z(x)Y(x)X(x)Spin, this cor-
 
      responds to a column-wise vectorization of a 3D array
 
      with dimensions ordered as [X Y Z].
 
 
Note: polyadic objects are returned, use inflate() to get the
 
      corresponding sparse matrix.
 
 
a.j.allami@soton.ac.uk
 
ilya.kuprov@weizmann.ac.il
 
mariagrazia.concilio@sjtu.edu.cn
 
  
 
==Notes==
 
==Notes==
 
 
1. The direct product order is Z(x)Y(x)X(x)Spin, this corresponds to a column-wise vectorization of a 3D array with dimensions ordered as [X Y Z].
 
1. The direct product order is Z(x)Y(x)X(x)Spin, this corresponds to a column-wise vectorization of a 3D array with dimensions ordered as [X Y Z].
  
Line 44: Line 28:
  
 
==See also==
 
==See also==
 
+
[[v2fplanck.m]], [[hydrodynamics.m]], [[imaging.m]], [[polyadic/inflate.m]], [[mri_2d_plot.m]], [[ngridpts.m]], [[phantoms.m]], [[Imaging_module]]
[[v2fplanck.m]], [[hydrodynamics.m]], [[imaging.m]]
 
 
 
  
 
''Version 2.1, authors: [[Ilya Kuprov]], [[Ahmed Allami]]''
 
''Version 2.1, authors: [[Ilya Kuprov]], [[Ahmed Allami]]''
 
==Description==
 
 
The cell array contains {Gx,Gy,Gz}, which should simply be added to the Hamiltonian with appropriate coefficients. Gradients are assumed to be linear and centered on the middle of the sample.
 

Latest revision as of 19:36, 6 June 2026

Returns the magnetic field gradient operators used by the imaging module within the Fokker-Planck formalism; the output cell array contains {Gx,Gy,Gz}, which should be added to the Hamiltonian with appropriate coefficients, and gradients are assumed linear and centred on the middle of the sample.

Syntax

    G=g2fplanck(spin_system,parameters)

Parameters

  parameters.dims    - a vector with one, two or three 
                       elements giving the dimensions
                       of the box, metres

  parameters.npts    - a vector with one, two or three
                       elements giving number of points
                       in each dimension of the box

Outputs

  G - a cell array with the three gradient operators 
      ordered as {Gx,Gy,Gz}, normalised to 1 T/m, empty
      matrices for non-exitent dimensions

Notes

1. The direct product order is Z(x)Y(x)X(x)Spin, this corresponds to a column-wise vectorization of a 3D array with dimensions ordered as [X Y Z].

2. Polyadic objects are returned, use polyadic/inflate.m to get the corresponding sparse matrix.

See also

v2fplanck.m, hydrodynamics.m, imaging.m, polyadic/inflate.m, mri_2d_plot.m, ngridpts.m, phantoms.m, Imaging_module

Version 2.1, authors: Ilya Kuprov, Ahmed Allami