[Eeglablist] ICA: freezing when choosing learning rate

[Elliot Cohen]

Hi,

In one of the datasets that I am trying to compute ICA for, I did several
preprocessing steps to clean the data slightly before ICA. Namely, I removed
any linear trend in the data, subtracted the ensemble mean (the mean of each
time point across trials), and divided by the ensemble standard deviation.
After this is done, I try to compute an ICA decomposition using the runica
algorithm, the algorithm seems to get stuck trying to find a learning rate.
This is not to say that the machine freezes, but more like it gets stuck in
an internal loop that it isn't able to break out of. Has anyone ever
experienced this problem? The dataset is approximately 70 trials, each trial
has 7,144 samples, and 64 channels. I am using a 3.2 gHz machine with 1 GB
of memory running Mandrake. I have been using eeglab for the last year or so
to decompose data and have never run into anything like this, does anyone
have any ideas?

Thanks,

Elliot
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