(math-random-digit): Rename to `math-random-three-digit-number'.

(math-random-digits): Don't depend on representation of integers.

diff --git a/lisp/calc/calc-comb.el b/lisp/calc/calc-comb.el
index 7bda99724267d99bff6f07c229cb8f8a410650f5..ede04fd50327162ab62dca00decafa2c7dfc1f1d 100644 (file)
--- a/lisp/calc/calc-comb.el
+++ b/lisp/calc/calc-comb.el
@@ -615,7 +615,8 @@
 ;;; Avoid various pitfalls that may lurk in the built-in (random) function!
 ;;; Shuffling algorithm from Numerical Recipes, section 7.1.
 (defvar math-random-last)
-(defun math-random-digit ()
+(defun math-random-three-digit-number ()
+  "Return a random three digit number."
   (let (i)
     (or (and (boundp 'var-RandSeed) (eq var-RandSeed math-last-RandSeed))
        (math-init-random-base))
@@ -635,17 +636,17 @@
 
 ;;; Produce an N-digit random integer.
 (defun math-random-digits (n)
-  (cond ((<= n 6)
-        (math-scale-right (+ (* (math-random-digit) 1000) (math-random-digit))
-                          (- 6 n)))
-       (t (let* ((slop (% (- 900003 n) 3))
-                 (i (/ (+ n slop) 3))
-                 (digs nil))
-            (while (> i 0)
-              (setq digs (cons (math-random-digit) digs)
-                    i (1- i)))
-            (math-normalize (math-scale-right (cons 'bigpos digs)
-                                              slop))))))
+  "Produce a random N digit integer."
+  (let* ((slop (% (- 3 (% n 3)) 3))
+         (i (/ (+ n slop) 3))
+         (rnum 0))
+    (while (> i 0)
+      (setq rnum 
+            (math-add
+             (math-random-three-digit-number)
+             (math-mul rnum 1000)))
+      (setq i (1- i)))
+    (math-normalize (math-scale-right rnum slop))))
 
 ;;; Produce a uniformly-distributed random float 0 <= N < 1.
 (defun math-random-float ()