There is a problem somewhere which manifests itself in dpart,
though I think its roots must be somewhere else.
To begin with, look at the docs to rembox and you will see (among
other things):
(%i1) expr: (a*d - b*c)/h^2 + sin(%pi*x);
a d - b c
(%o1) sin(%pi x) + ---------
2
h
(%i2) dpart (dpart (expr, 1, 1), 2, 2);
""""""" a d - b c
(%o2) sin("%pi x") + ---------
""""""" """"
" 2"
"h "
""""
but dpart (dpart (expr, 1, 1), 2, 2);
give an error:
dpart fell off end.
-- an error. To debug this try debugmode(true);
which is no wonder, because you will see that somehow in
(%i4) dpart (expr, 1, 1);
a d - b c """""""
(%o4) --------- - sin(- "%pi x")
2 """""""
h
we have managed to introduce minus signs and switch from sin(x) to
- sin(-x).
Where does that come from? Has anybody got an idea?
'Andreas
--
Wherever I lay my .emacs, there's my $HOME.