;;; -*- Mode: Common-Lisp; Package: sys; Base: 8.; Patch-File: T -*-

;;; Reason: Modified rationalize-float to give up when result becomes greater than most-positive-double-float.[11135,11144]

;;;                           RESTRICTED RIGHTS LEGEND
;;;
;;; Use, duplication, or disclosure by the Government is subject to
;;; restrictions as set forth in subdivision (c)(1)(ii) of the Rights in
;;; Technical Data and Computer Software clause at 52.227-7013.
;;;
;;;   TEXAS INSTRUMENTS INCORPORATED      
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;;; Copyright (C) 1989 Texas Instruments Incorporated.
;;; All rights reserved.

;;; Written 05/23/90 08:36:50 by BERGER,
;;; while running on Pasteur from band LOD2
;;; With SYSTEM 6.32, VIRTUAL-MEMORY 6.3, EH 6.7, MAKE-SYSTEM 6.3, MICRONET 6.0, LOCAL-FILE 6.2,
;;;  BASIC-PATHNAME 6.4, NETWORK-SUPPORT-COLD 6.2, BASIC-NAMESPACE 6.7, NETWORK-NAMESPACE 6.1,
;;;  DISK-IO 6.3, DISK-LABEL 6.0, BASIC-FILE 6.11, MAC-PATHNAME 6.0, NETWORK-PATHNAME 6.2,
;;;  COMPILER 6.14, TV 6.25, DATALINK 6.0, CHAOSNET 6.6, GC 6.3, MEMORY-AUX 6.0, NVRAM 6.2,
;;;  SYSLOG 6.2, STREAMER-TAPE 6.6, UCL 6.0, INPUT-EDITOR 6.0, METER 6.1, ZWEI 6.16,
;;;  DEBUG-TOOLS 6.4, NETWORK-SUPPORT 6.1, NETWORK-SERVICE 6.2, DATALINK-DISPLAYS 6.0,
;;;  FONT-EDITOR 6.1, SERIAL 6.0, PRINTER 6.6, MAC-PRINTER-TYPES 6.2, PRINTER-TYPES 6.2,
;;;  IMAGEN 6.1, SUGGESTIONS 6.1, MAIL-DAEMON 6.6, MAIL-READER 6.8, TELNET 6.1, VT100 6.0,
;;;  NAMESPACE-EDITOR 6.4, PROFILE 6.3, VISIDOC 6.7, TI-CLOS 6.46, CLEH 6.5, IP 3.62,
;;;  Experimental CLX 6.11, CLUE 6.104, X11M 6.24, Experimental BUG 11.19,  microcode 648,
;;;  Band Name: rel6.0 1/23

#!C
; From file NUMBERS.LISP#> KERNEL; sys:
#8R SYSTEM#:
(COMPILER-LET ((*PACKAGE* (FIND-PACKAGE "SYSTEM"))
                          (SI:*LISP-MODE* :COMMON-LISP)
                          (*READTABLE* COMMON-LISP-READTABLE)
                          (SI:*READER-SYMBOL-SUBSTITUTIONS* *COMMON-LISP-SYMBOL-SUBSTITUTIONS*))
  (COMPILER#:PATCH-SOURCE-FILE "SYS: KERNEL; NUMBERS.#"


(DEFUN rationalize-float (x &optional (eps long-float-epsilon))
  (COND ((MINUSP x) (- (RATIONALIZE-FLOAT (- x) eps)))
	((ZEROP x) 0)
	(t (LET ((y ())
		 (a ())
		 (big (floor most-positive-double-float)))  ; DAB/BF 05-23-90
	     (DO ((xx x y)
		  (num (SETQ a (TRUNCATE x)) (+ (* a num) onum))
		  (den 1 (+ (* a den) oden))
		  (onum 1 num)
		  (oden 0 den))
		 ((OR (= xx a)
                      (> den big)  ; DAB/BF 05-23-90 When this is true , give up. Otherwise machine may be in a finite loop.
		      (<= (ABS (/ (- x (/ num den))
				  x))
			  eps))
		  (/ num den))			;Generate final result
	       (SETQ y (/ (- xx a))
		     a (TRUNCATE y)))))))
))