Hi:

I am trying to perform a first-level analysis using mkanalysis-sess and selxavg3-sess using data from one of my experiments and the steps described in the FsFastTutorial (http://surfer.nmr.mgh.harvard.edu/fswiki/FsFastTutorial ). I am able to complete the analysis using the tutorial data but on my data selxavg3 returns the following error:

... ...

In fast_selxavg3 at 212

Warning: Matrix is singular, close to singular or badly scaled. Results may be inaccurate. RCOND = NaN.

In fast_selxavg3 at 212

ntptot = 740, nX = 32, DOF = 708 Saving X matrix to /Users/eiji/exp/ FS_classic_oddball_2009/090407_Kitamichi/bold/classodd-gamma-fwhm8/ Xtmp.mat ??? Error using ==> svd Input to SVD must not contain NaN or Inf.

Error in ==> cond at 40 s = svd(A);

Error in ==> fast_selxavg3 at 248 XCond = cond(XtX);

...

2009-04-20 13:47:07.771 MATLAB[82205:60b] Process manager already

initialized -- can't fully enable headless mode. ------------------------------------------ ERROR: fast_selxavg3() failed\n

This only happens when I choose the Gamma function or the SPM hemodynamic response function in mkanalysis-sess. If the chosen function is the finite-impulse response, selxavg3 finishes with no major problems.

I am clueless about what could be causing this error. If you have any ideas or need more detailed information, please, let me know!

Thanks very much.

Eiji

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