On Jan 19, 2008 1:00 PM, Eldon Eller <[EMAIL PROTECTED]> wrote: > We may have occasion to evaluate an expression such as my example > that results in 0%0 without realizing it. I.e., we do not separately evaluate > numeratorand denominator. In such cases, J returns 0, which is the wrong > answer, as demonstrated by application of l'Hospital's rule.
Sorry, no. l'Hospital's rule is a statement about a limit condition. l'Hospital's rule requires no specific value for the result of 0%0. > J gives no warning that there is anything pathological in the expression. More generally, numerical analysis requires some expertise. If you do not check your results you will have all sorts of problems, in part because of the limitations of number representations such as floating point. But other errors are also possible. Meanwhile, using the result 0 for the result of 0%0 is analogous to using the result 0 for the result of arc sin 0. In both cases you have an infinite number of valid answers, but 0 is a simple answer. -- Raul ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
