Maxima Function
inpart (expr, n_1, ..., n_k)
is similar to part
but works on the internal
representation of the expression rather than the displayed form and
thus may be faster since no formatting is done. Care should be taken
with respect to the order of subexpressions in sums and products
(since the order of variables in the internal form is often different
from that in the displayed form) and in dealing with unary minus,
subtraction, and division (since these operators are removed from the
expression). part (x+y, 0)
or inpart (x+y, 0)
yield +
, though in order to
refer to the operator it must be enclosed in "s. For example
... if inpart (%o9,0) = "+" then ...
.
Examples:
(%i1) x + y + w*z; (%o1) w z + y + x (%i2) inpart (%, 3, 2); (%o2) z (%i3) part (%th (2), 1, 2); (%o3) z (%i4) 'limit (f(x)^g(x+1), x, 0, minus); g(x + 1) (%o4) limit f(x) x -> 0- (%i5) inpart (%, 1, 2); (%o5) g(x + 1)