Is there any nipype interface for avscale (FSL script)?

Question

I am trying to use nipype to analyze transformation matrixes that were created by FSL. FSL has a script called "avscale" that analyzes those transformation matrixes (*.mat files). I was wondering whether nipype has any interface that wrap that script and enable to work with its output.

Thanks

Answer 1

Based on the docs and the current source the answer is no. Also, avscale has also not been mentioned on the nipy-devel mailing list since at least last February. It's possible that Nipype already wraps something else that does this (perhaps with a matlab wrapper?) You could try opening an issue or asking the the mailing list.

As long as you're trying to use Python (with nipype and all), maybe the philosophy of the nipype project is that you should just use numpy/scipy for this? Just a guess, I don't know the functions to replicate this output with those tools. It's also possible that no one has gotten around to adding it yet.

For the uninitiated, avscale takes this affine matrix:

1.00614 -8.39414e-06  0          -0.757356  
0        1.00511     -0.00317841 -0.412038  
0        0.0019063    1.00735    -0.953364  
0        0            0           1  

and yields this or similar output:

Rotation & Translation Matrix:
1.000000 0.000000 0.000000 -0.757356 
0.000000 0.999998 -0.001897 -0.412038 
0.000000 0.001897 0.999998 -0.953364 
0.000000 0.000000 0.000000 1.000000 

Scales (x,y,z) = 1.006140 1.005112 1.007354 

Skews (xy,xz,yz) = -0.000008 0.000000 -0.001259 

Average scaling = 1.0062

Determinant = 1.01872
Left-Right orientation: preserved

Forward half transform =
1.003065 -0.000004 -0.000000 -0.378099 
0.000000 1.002552 -0.001583 -0.206133 
0.000000 0.000951 1.003669 -0.475711 
0.000000 0.000000 0.000000 1.000000 

Backward half transform =
0.996944 0.000004 0.000000 0.376944 
0.000000 0.997452 0.001575 0.206357 
0.000000 -0.000944 0.996343 0.473777 
0.000000 0.000000 0.000000 1.000000