[MINC-users] mincdefrag arguments

[Alex Zijdenbos]

This one is mostly for Claude, but just in case it has affected anybody I
figured I'd raise it here.

The mincdefrag help text states that the allowable values for this "number
of neighbors" value are (6, 19, 27), which is inconsistent (19 and 27
include the center voxel, 6 does not).

Where this matters is that I just realized that mincdefrag actually doesn't
check these values, and *silently (ack) falls back to '6' for anything that
is not 19 or 27*.

I for one have used (by force of habit or logic or consistency with
mincmorph) '26' in quite a number of mincdefrag calls, and I am now
realizing that those were all silently using a 6-neighbor kernel :(

I suggest we change the help text to read (1, 18, 26); and, for backward
compatibility, change the bit where it checks this value to accept both 18
and 19 for stencil=2; 26 and 27 for stencil=3, and throws an error for
anything that is not (6, 18, 19, 26, 27);

-- A