From 3843711abd8d599206acbcc0aa97dae708285416 Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Mon, 4 Nov 2019 23:19:36 -0800 Subject: [PATCH] Simplify calculator-expt * lisp/calculator.el (calculator-expt): Simplify, now that expt does the right thing if the first arg is -1, 0, or 1. --- lisp/calculator.el | 28 ++++------------------------ 1 file changed, 4 insertions(+), 24 deletions(-) diff --git a/lisp/calculator.el b/lisp/calculator.el index 281151c7c25..fab365d5f28 100644 --- a/lisp/calculator.el +++ b/lisp/calculator.el @@ -1619,30 +1619,10 @@ To use this, apply a binary operator (evaluate it), then call this." "Compute X^Y, dealing with errors appropriately." (condition-case nil (expt x y) - (domain-error 0.0e+NaN) - (range-error - (cond ((and (< x 1.0) (> x -1.0)) - ;; For small x, the range error comes from large y. - 0.0) - ((and (> x 0.0) (< y 0.0)) - ;; For large positive x and negative y, the range error - ;; comes from large negative y. - 0.0) - ((and (> x 0.0) (> y 0.0)) - ;; For large positive x and positive y, the range error - ;; comes from large y. - 1.0e+INF) - ;; For the rest, x must be large and negative. - ;; The range errors come from large integer y. - ((< y 0.0) - 0.0) - ((eq (logand (truncate y) 1) 1) ; expansion of cl `oddp' - ;; If y is odd - -1.0e+INF) - (t - ;; - 1.0e+INF))) - (error 0.0e+NaN))) + (overflow-error + (if (or (natnump x) (cl-evenp y)) + 1.0e+INF + -1.0e+INF)))) (defun calculator-fact (x) "Simple factorial of X." -- 2.39.5