only two components!

Sameer Walawalkar sameer at ANDREW.CMU.EDU
Fri Feb 23 21:01:10 CET 2007


Hi,

please add

case 'FASTICA'
     status = exist('fastica','file');

to your hastoolbox file.

but after I do that, I get only two components for 306 channel Neuromag
data! It might be related to my crude adding shown above, but...


cfg.method = 'fastica';

>>
compRR_one_sss_fastica = componentanalysis(cfg,dataRR_One)
selecting 307 channels
baseline correcting data
concatenating data..............................
concatenated data matrix size 307x120030
starting decomposition using fastica
Number of signals: 307
Number of samples: 120030
Calculating covariance...
Reducing dimension...
Selected [ 2 ] dimensions.
Smallest remaining (non-zero) eigenvalue [ 1.04859e+08 ]
Largest remaining (non-zero) eigenvalue [ 2.68806e+09 ]
Sum of removed eigenvalues [ 8.96883e-05 ]
[ 100 ] % of (non-zero) eigenvalues retained.
Whitening...
Check: covariance differs from identity by [ 1.9984e-15 ].
Used approach [ defl ].
Used nonlinearity [ pow3 ].
Starting ICA calculation...
IC 1 .....computed ( 5 steps )
IC 2 ..computed ( 2 steps )
Done.
Adding the mean back to the data.
total time in componentanalysis 46.9 seconds

compRR_one_sss_fastica =

       fsample: 1000
          time: {1x30 cell}
         trial: {1x30 cell}
         label: {307x1 cell}
     topolabel: {307x1 cell}
          topo: [307x2 double]
           cfg: [1x1 struct]

best,
sameer



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