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Bug 86 - topoplotER cfg,interplimits = 'electrodes' does not plot outside of head
| Status | CLOSED FIXED |
| Reported | 2010-05-31 10:40:00 +0200 |
| Modified | 2011-01-14 13:31:15 +0100 |
| Product: | FieldTrip |
| Component: | core |
| Version: | unspecified |
| Hardware: | PC |
| Operating System: | Windows |
| Importance: | P5 normal |
| Assigned to: | Cristiano Micheli |
| URL: | |
| Tags: | |
| Depends on: | |
| Blocks: | |
| See also: |
Roemer van der Meij - 2010-05-31 10:40:09 +0200
Created attachment 4 zip-file containing pictures mentioned Dear Fieldtrippers, I am having an issue with creating topoplots of time-frequency data acquired on an EGI system and processed in Fieldtrip, and I was wondering if anyone could help. Everything works great (this toolbox has been wonderful to use in general!) except that the colors that represent power are not interpolating to electrodes that are lower than the origin. Unfortunately, using the default option for cfg.projection = 'orthographic' for ft_prepare_layout, seems to greatly distort the layout for these data, probably because I have too few electrodes. A better option for me seems to be cfg.projection = 'polar', and I am fine with those few electrodes appearing outside of the head. However, the data corresponding to those electrodes is not there - I suspect that there is a problem at the level of cfg.interplimits. This is the code I'm using: cfg = []; cfg.rotate = 0; cfg.projection = 'polar'; newlay=ft_prepare_layout(cfg, bin1); cfg = []; cfg.layout = newlay; cfg.yparam = 'freq'; cfg.xlim= [0.150 0.150]; cfg.ylim= [13 30]; cfg.zlim = [-0.10 0.10]; cfg.highlight = 'on'; cfg.baseline = 'no'; cfg.commentpos = 'title'; cfg.shading = 'interp'; cfg.interplimits = 'electrodes'; %Should work here? cfg.style = 'straight'; cfg.zparam = 'powspctrm'; cfg.fontsize = 12; cfg.gridscale = 100; ft_topoplotTFR(cfg, bin1); According to the documentation, specifying cfg.interplimits = 'electrodes' should achieve what I want here, but it still does not interpolate the plot outside of the head. Attached are some images generated with different cfg.interplimits and cfg.projection options. I have tried upgrading to the most recent release of FT, but it doesn't change the outcome. Any and all insight would be greatly appreciated. Best, Reyna
Roemer van der Meij - 2010-11-03 16:22:13 +0100
I could not work out the specifics, but it appears the 'anatomical' mask is generated/modified inappropriately in ft_plot_topo.m, causing the data-interpolation to be limited to the head-shape in the end, instead of e.g. a circle around all of the electrodes with some added width.
Cristiano Micheli - 2010-12-14 15:28:12 +0100
(In reply to comment #1) > I could not work out the specifics, but it appears the 'anatomical' mask is > generated/modified inappropriately in ft_plot_topo.m, causing the > data-interpolation to be limited to the head-shape in the end, instead of e.g. > a circle around all of the electrodes with some added width. Dear all 7 EEG templates have been added which comply with the EGI standards (see fieldtrip/templates directory, .stp files for 32/64/65/128/129/256/257 contacts) To import and use them type: cfg = []; cfg.elecfile = 'GSN-HydroCel-256.sfp'; lay = ft_prepare_layout(cfg) figure,ft_plot_lay(lay) This should solve the problem of peripheral electrodes' interpolation, since they are included inside the external outline. Credit: thanks to Giovanni Piantoni Best Cristiano