Probably because SPM uses "NaN" values to effect masking within the
image (which isn't really allowed by the format).
If you use the -nan flag in avwmaths++ it will remove those.
Cheers.
On 10 May 2007, at 19:16, Jonathan Hakun wrote:
> I'm having a hard time figuring out why these are coming up "not a
> number".
>
> I converted a set of t-stat images from an SPM analysis to z-stat
> with some
> help from the e-mail list. I also resliced my zstats to match the
> mask and
> the background-image for use w/ easythresh. When I use easythresh, my
> p-value and -logp values are coming up nan for every cluster (as
> evidenced
> in the generated table.txt).
>
> I've used easythresh with data that had much higher z-values and
> larger
> extents before at similar thresholds with success.
>
> Any ideas as to why this might happen?
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Stephen M. Smith, Professor of Biomedical Engineering
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FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK
+44 (0) 1865 222726 (fax 222717)
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