Why doesn't pause work in function? Why errors from plot?

[J Stasko]

Sorry to be so obtrusive, but I need help!!!  Thanks!

~~~~~~~~~~PROBLEM STATEMENT:

I have actually two problems.

-> My .m file does  *not*  pause when it comes to the "pause"
statement.  Why is this?
-> plot gives me an error where there is no error.

***********
~~~~~~~~~~FUNCTION WHICH CAUSES PROBLEM:
Here is the function:

function plottrack(x)
  [slices,values] = size(x)
  for i = 0 : ((values-3)/6)-2
  i
  pause
  plot(x(:,(i*6)+4),x(:,(i*6)+5))
  pause
  endfor
endfunction

************
~~~~~~~~~~~OUTPUT:
Here is the output:

octave-3.4.0:2> plottrack(snaps)
slices =  31
values =  183
error: plottrack: A(I,J): column index out of bounds; value 183 out of bound 183
error: called from:
error:   /Users/johns/Programming/diameter/plottrack.m at line 4, column 4
octave-3.4.0:2>

*****************
~~~~~~~~~~~VERSION INFORMATION:

Here is my version information (yes, it's a new load from macports)

octave-3.4.0:1> ver
----------------------------------------------------------------------
GNU Octave Version 3.4.0
GNU Octave License: GNU General Public License
Operating System: Darwin 10.8.0 Darwin Kernel Version 10.8.0: Tue Jun
7 16:33:36 PDT 2011; root:xnu-1504.15.3~1/RELEASE_I386 i386
----------------------------------------------------------------------
no packages installed.
octave-3.4.0:2> system("uname -a")
Darwin s-3.local 10.8.0 Darwin Kernel Version 10.8.0: Tue Jun  7
16:33:36 PDT 2011; root:xnu-1504.15.3~1/RELEASE_I386 i386
ans = 0
octave-3.4.0:3>

Ben also asked,

octave-3.4.0:4> which plot
`plot' is a function from the file
/Applications/Octave.app/Contents/Resources/share/octave/3.4.0/m/plot/plot.m

*************
~~~~~~~~~~HISTORY:
Ben recommended I try this and I still get an error:

octave-3.4.0:3> plottrack(rand(31,183))
slices =  31
values =  183
error: plottrack: A(I,J): column index out of bounds; value 183 out of bound 183
error: called from:
error:   /Users/johns/Programming/diameter/plottrack.m at line 4, column 4

**************

Dima had the following comment:


>>I suspect a more general problem
>>
>>John -- does the following code work on your machine ?
>>
>>a = rand(200);
>>b = inv(a)*a;
>>trace(b)
>>
>>Dmitri.

But this works, b is 200:

***********************************PLEASE HELP*************************

Thanks!!!

-John