ENH - updated source2grid, outside is not always present. Also updated test script

Author: robertoostenveld

test/test_bug1746.m

@@ -14,11 +14,11 @@
 sourcemodel.outside = setdiff(1:prod(sourcemodel.dim),sourcemodel.inside);
 meglabel    = ft_channelselection('MEG', freq.label);
 
-cfg         = [];
-cfg.vol     = vol;
-cfg.grid    = sourcemodel;
-cfg.channel = meglabel;
-leadfield1  = ft_prepare_leadfield(cfg, freq);
+cfg           = [];
+cfg.headmodel = vol;
+cfg.grid      = sourcemodel;
+cfg.channel   = meglabel;
+leadfield1    = ft_prepare_leadfield(cfg, freq);
 assert(isfield(leadfield1, 'label'));
 
 shuffle     = randperm(numel(meglabel));
@@ -33,12 +33,12 @@
 % leadfield.leadfield.
 
 cfg = [];
-cfg.method = 'dics';
-cfg.vol    = vol;
-cfg.grid   = leadfield1;
-cfg.frequency = 5;
+cfg.method      = 'dics';
+cfg.headmodel   = vol;
+cfg.grid        = leadfield1;
+cfg.frequency   = 5;
 cfg.dics.lambda = '10%';
-cfg.channel = meglabel;
+cfg.channel     = meglabel;
 source1 = ft_sourceanalysis(cfg, freq);
 
 cfg.channel = meglabel(1:2:end);

utilities/ft_source2grid.m

@@ -33,17 +33,7 @@
 
 ft_defaults
 
-% these are always supposed to be present
-grid.pos     = source.pos;
-grid.inside  = source.inside;
-grid.outside = source.outside;
-
-% these are optional
-try, grid.xgrid   = source.xgrid; end
-try, grid.ygrid   = source.ygrid; end
-try, grid.zgrid   = source.zgrid; end
-try, grid.dim     = source.dim;   end
-try, grid.tri     = source.tri;   end % only in case of a tesselated/triangulated cortical sheet source model
+grid = keepfields(source, {'pos', 'tri', 'inside', 'outside', 'xgrid', 'ygrid', 'zgrid', 'dim'});
 
 if ~isfield(grid, 'dim') && isfield(grid, 'xgrid') && isfield(grid, 'ygrid') && isfield(grid, 'zgrid')
   grid.dim = [length(grid.xgrid) length(grid.ygrid) length(grid.zgrid)];
@@ -57,6 +47,8 @@
   error('single trial filters are not supported here');
 end
 
-if isfield(source, 'leadfield')
+if issubfield(source, 'leadfield')
   grid.leadfield = source.leadfield;
+elseif issubfield(source, 'avg.leadfield')
+  grid.leadfield = source.avg.leadfield;
 end