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--- reference:ft_compute_leadfield [2018/08/23 14:43]
+++ reference:ft_compute_leadfield [2018/08/23 14:43] (current)
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+=====  FT_COMPUTE_LEADFIELD =====
+Note that this reference documentation is identical to the help that is displayed in MATLAB when you type "help ft_compute_leadfield".
+<html><pre>
+  <a href=/reference/ft_compute_leadfield><font color=green>FT_COMPUTE_LEADFIELD</font></a> computes a forward solution for a dipole in a a volume
+  conductor model. The forward solution is expressed as the leadfield
+  matrix (Nchan*3), where each column corresponds with the potential or field
+  distributions on all sensors for one of the x,y,z-orientations of the
+  dipole.
+  Use as
+    [lf] = ft_compute_leadfield(dippos, sens, headmodel, ...)
+  with input arguments
+    dippos       = position dipole (1*3 or Ndip*3)
+    sens      = structure with gradiometer or electrode definition
+    headmodel = structure with volume conductor definition
+  The headmodel represents a volume conductor model, its contents
+  depend on the type of model. The sens structure represents a sensor
+  array, i.e. EEG electrodes or MEG gradiometers.
+  It is possible to compute a simultaneous forward solution for EEG and MEG
+  by specifying sens and grad as two cell-arrays, e.g.
+    sens       = {senseeg, sensmeg}
+    headmodel  = {voleeg,  volmeg}
+  This results in the computation of the leadfield of the first element of
+  sens and headmodel, followed by the second, etc. The leadfields of the
+  different imaging modalities are subsequently concatenated.
+  Additional input arguments can be specified as key-value pairs, supported
+  optional arguments are
+    'reducerank'      = 'no' or number
+    'normalize'       = 'no', 'yes' or 'column'
+    'normalizeparam'  = parameter for depth normalization (default = 0.5)
+    'weight'          = number or 1xN vector, weight for each dipole position (default = 1)
+    'backproject'     = 'yes' (default) or 'no', in the case of a rank reduction
+                        this parameter determines whether the result will be
+                        backprojected onto the original subspace
+  The leadfield weight may be used to specify a (normalized)
+  corresponding surface area for each dipole, e.g. when the dipoles
+  represent a folded cortical surface with varying triangle size.
+  Depending on the specific input arguments for the sensor and volume, this
+  function will select the appropriate low-level EEG or MEG forward model.
+  The leadfield matrix for EEG will have an average reference over all the
+  electrodes.
+  The supported forward solutions for MEG are
+    single sphere (Cuffin and Cohen, 1977)
+    multiple spheres with one sphere per channel (Huang et al, 1999)
+    realistic single shell using superposition of basis functions (Nolte, 2003)
+    leadfield interpolation using a precomputed grid
+    boundary element method (BEM)
+  The supported forward solutions for EEG are
+    single sphere
+    multiple concentric spheres (up to 4 spheres)
+    leadfield interpolation using a precomputed grid
+    boundary element method (BEM)
+  See also <a href=/reference/ft_prepare_vol_sens><font color=green>FT_PREPARE_VOL_SENS</font></a>, <a href=/reference/ft_headmodel_asa><font color=green>FT_HEADMODEL_ASA</font></a>, <a href=/reference/ft_headmodel_bemcp><font color=green>FT_HEADMODEL_BEMCP</font></a>,
+  <a href=/reference/ft_headmodel_concentricspheres><font color=green>FT_HEADMODEL_CONCENTRICSPHERES</font></a>, <a href=/reference/ft_headmodel_dipoli><font color=green>FT_HEADMODEL_DIPOLI</font></a>, <a href=/reference/ft_headmodel_halfspace><font color=green>FT_HEADMODEL_HALFSPACE</font></a>,
+  <a href=/reference/ft_headmodel_infinite><font color=green>FT_HEADMODEL_INFINITE</font></a>, <a href=/reference/ft_headmodel_localspheres><font color=green>FT_HEADMODEL_LOCALSPHERES</font></a>, <a href=/reference/ft_headmodel_openmeeg><font color=green>FT_HEADMODEL_OPENMEEG</font></a>,
+  <a href=/reference/ft_headmodel_singleshell><font color=green>FT_HEADMODEL_SINGLESHELL</font></a>, <a href=/reference/ft_headmodel_singlesphere><font color=green>FT_HEADMODEL_SINGLESPHERE</font></a>,
+  <a href=/reference/ft_headmodel_halfspace><font color=green>FT_HEADMODEL_HALFSPACE</font></a>
+</pre></html>