Hello All,

I have a very basic question about to3d. I have a dataset which on running 3dinfo gives me

Dataset File: Volume+orig
Identifier Code: XYZ_3I-mbbZWSeW65pvhlBmL8Q Creation Date: Wed Nov 24 11:56:38 2004
Dataset Type: Spoiled GRASS (-spgr)
Byte Order: LSB_FIRST [this CPU native = LSB_FIRST]
Storage Mode: BRIK file
Data Axes Orientation:
first (x) = Anterior-to-Posterior
second (y) = Superior-to-Inferior
third (z) = Left-to-Right [-orient ASL]
R-to-L extent: -90.200 [R] -to- 88.300 [L] -step- 1.500 mm [120 voxels]
A-to-P extent: -119.531 [A] -to- 119.531 [P] -step- 0.938 mm [256 voxels]
I-to-S extent: -119.531 -to- 119.531 [S] -step- 0.938 mm [256 voxels]
Number of values stored at each pixel = 1
-- At sub-brick #0 '#0' datum type is short: 0 to 1360

HISTORY
to3d -spgr -prefix Volume -session Results -2swap -view orig -xFOV 120.0A-120.0P -yFOV 120.0S-120.0I -zSLAB 88.3L-90.2R '3D:0:8432:256:256:1:Volume/I*'



Could someone please tell me what does A-P extent mean: Does it mean the distance between the centers of the voxels in the A-P direction?

The reason this is confusing me is because the FOV is 240. and so as I had entered 120 into A and P in my command line, I am still getting 119.531A-119.531P which adds upto 239.062 and not 240.

239.062/0.938 gives me 255 and hence I thought that the A-P extent is probably the distance between the centers.


Please do help. thanks

N