tapas_physio_pca -> no voxel limitation

[benoitberanger]

This PR responds to #162

CHANGE : tapas_physio_pca

This function now uses the covariance matrix instead of the matrix itself. This strategy is inpired by spm_regions function.

CHANGE : tapas_physio_create_noise_rois_regressors

The function have minor modifications due to the PCA rework. However :

• The "force coregister & reslice" warning is now a normal log message
• Logs added to check the number of voxels remaining in the ROI after threshold & erosion.

NEW : function tapas_physio_interactive_noiseROI_mask

This function will load a mask and display it using _spmorthviews, apply a threshold + erosion then display the result using an overlay. The noiseROI volume (the overlay) remains in memory, no volume is written. Maybe a feature to add ? A panel is added on spm_orthviews so the threshold and erosion level can be changed and the result visualized dynamicaly.

DELETE : tapas_physio_pca_test

The function have been removed, since the approach have changed (covariance matrix) This is a discussion the to have with the devs (@mrikasper). I'm opened to keep the test function, even though it needs to be complitly reworked to keep the old appreach and the new.

[benoitberanger]

TODO

• interactive : return the values for latter usage
• unittest : provide dataset and scripts to check current and proposed PCA implementation
• when "not enough voxels" still indicate how many before stopping execution

[mrikasper]

Dear Benoit,

My apologies, but I didn't have enough time to include your PR into the upcoming TAPAS release. I am still working with Johanna Bayer on the summer project to improve PhysIO, but it will take a couple of weeks to overhaul everything. I will let you know once we integrate your PR.

All the best, Lars

[benoitberanger]

• [x] interactive : return the values for latter usage fc8a3a2
• [ ] unittest : provide dataset and scripts to check current and proposed PCA implementation
• [x] when "not enough voxels" still indicate how many before stopping execution eff3868