Application Guide

98 Alphabetical Listing
limit() or lim()
Catalog >
Limits at positive ∞ and at negative ∞ are
always converted to one-sided limits from
the finite side.
Depending on the circumstances, limit()
returns itself or undef when it cannot
determine a unique limit. This does not
necessarily mean that a unique limit does
not exist. undef means that the result is
either an unknown number with finite or
infinite magnitude, or it is the entire set of
such numbers.
limit() uses methods such as L’Hopital’s
rule, so there are unique limits that it
cannot determine. If Expr1 contains
undefined variables other than Var, you
might have to constrain them to obtain a
more concise result.
Limits can be very sensitive to rounding
error. When possible, avoid the
Approximate setting of the Auto or
Approximate mode and approximate
numbers when computing limits.
Otherwise, limits that should be zero or
have infinite magnitude probably will not,
and limits that should have finite non-zero
magnitude might not.
LinRegBx
Catalog >
LinRegBx X,Y[,[Freq][,Category,Include]]
Computes the linear regression y = a+b•x on
lists X and Y with frequency Freq. A
summary of results is stored in the
stat.results variable. (See page 177.)
All the lists must have equal dimension
except for Include.
X and Y are lists of independent and
dependent variables.