2 ;;; Copyright (c) 2005--2007, by A.J. Rossini <blindglobe@gmail.com>
3 ;;; See COPYRIGHT file for any additional restrictions (BSD license).
4 ;;; Since 1991, ANSI was finally finished. Edited for ANSI Common Lisp.
6 ;;;; lsfloat -- Floating point specs and transcendental functions
8 ;;;; Copyright (c) 1991, by Luke Tierney. Permission is granted for
11 ;;;; Common Lisp allows for four different floating point types that need
12 ;;;; not be distinct. For statistical work, the type I prefer to use is
13 ;;;; the one that is closest to a C double. This type is named stat-float.
14 ;;;; By setting the variable *read-default-float-format* to this type, you
15 ;;;; insure that data entered as floating point data is read in with this
16 ;;;; type. The problem arises with data read as integers that is passed to
17 ;;;; a transcendental, like sqrt. Floating point contagion rules say these
18 ;;;; integers are to be converted to type single-float. Unless single-float
19 ;;;; is equivalent to C double, as it is in Mac CL and KCL, this is not
20 ;;;; what I want. Hence this file redefines the transcendentals to first
21 ;;;; coerce their arguments to stat-float before applying the built-in
24 ;;;; No actual modifications to the transcendentals are needed if
25 ;;;; single-float is the same as stat-float. The fearure
26 ;;;; :stat-float-is-double-float is used to indicate this.
29 ;;;; In (A)KCL the type short-float corresponds to C float and the types
30 ;;;; single-float, double-float and long-float correspond to C double.
31 ;;;; But in the implementation of the transcendentals (A)KCL coerces
32 ;;;; rationals to short-float, not single-float. CLtL1 is a little vague
33 ;;;; on this (it talks about "single precision") but CLtL2 clarifies that
34 ;;;; rationals should produce single-float results. So (A)KCL is wrong, at
35 ;;;; least relative to the clarification in CLtL2. I therefore decided
36 ;;;; to fix (A)KCL in files c/num_sfun.c and lsp/numlib.lsp. If these
37 ;;;; fixes are applied, the feature :stat-float-is-double-float should be
41 ;;; ======== From the CLHS ==========
43 ;; Type SHORT-FLOAT, SINGLE-FLOAT, DOUBLE-FLOAT, LONG-FLOAT
47 ;; short-float: short-float, float, real, number, t
50 ;; single-float: single-float, float, real, number, t
52 ;; double-float: double-float, float, real, number, t
54 ;; long-float: long-float, float, real, number, t
56 ;; Description: For the four defined subtypes of type float, it is true
57 ;; that intermediate between the type short-float and the type long-float
58 ;; are the type single-float and the type double-float. The precise
59 ;; definition of these categories is implementation-defined. The
60 ;; precision (measured in ``bits'', computed as p log 2b) and the
61 ;; exponent size (also measured in ``bits,'' computed as log 2(n+1),
62 ;; where n is the maximum exponent value) is recommended to be at least
63 ;; as great as the values in the next figure. Each of the defined
64 ;; subtypes of type float might or might not have a minus zero.
67 ;; Format Minimum Precision Minimum Exponent Size
69 ;; Short 13 bits 5 bits
70 ;; Single 24 bits 8 bits
71 ;; Double 50 bits 8 bits
72 ;; Long 50 bits 8 bits
74 ;; Figure 12-12. Recommended Minimum Floating-Point Precision and Exponent Size
76 ;; There can be fewer than four internal representations for floats. If
77 ;; there are fewer distinct representations, the following rules apply:
79 ;; If there is only one, it is the type single-float. In this
80 ;; representation, an object is simultaneously of types single-float,
81 ;; double-float, short-float, and long-float.
83 ;; Two internal representations can be arranged in either of the
86 ;; Two types are provided: single-float and short-float. An object is
87 ;; simultaneously of types single-float, double-float, and long-float.
89 ;; Two types are provided: single-float and double-float. An object is
90 ;; simultaneously of types single-float and short-float, or double-float
93 ;; Three internal representations can be arranged in either of the
96 ;; Three types are provided: short-float, single-float, and
97 ;; double-float. An object can simultaneously be of type double-float and
100 ;; Three types are provided: single-float, double-float, and
101 ;; long-float. An object can simultaneously be of types single-float and
108 (defpackage :lisp-stat-float
110 (:export
+stat-float-typing
+ +stat-cfloat-typing
+ +stat-float-template
+
115 make-base-trans-fun-2 make-base-trans-fun
117 BASE-LOG BASE-EXP BASE-EXPT BASE-SQRT BASE-SIN BASE-COS
118 BASE-TAN BASE-ASIN BASE-ACOS BASE-ATAN BASE-SINH
119 BASE-COSH BASE-TANH BASE-ASINH BASE-ACOSH BASE-ATANH
120 BASE-ABS BASE-PHASE BASE-FFLOOR BASE-FCEILING BASE-FTRUNCATE
121 BASE-FROUND BASE-SIGNUM BASE-CIS
))
123 (in-package #:lisp-stat-float
)
125 ;; This should technically be conditionalized to the Lisp
126 ;; implementation, i.e.
127 #+sbcl
(pushnew :stat-float-is-double-float
*features
*)
128 #+cmu
(pushnew :stat-float-is-double-float
*features
*)
129 #+clisp
(pushnew :stat-float-is-double-float
*features
*)
130 ;; etc... the above need to be verified!
132 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
133 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
135 ;;;; Constants determining default floating point type for statistical
136 ;;;; operations. This type generally corresponds to a C double.
138 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
139 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
141 ;; Why do we do this instead of defparameter? mostly to allow for doc
142 ;; defs as well as to minimize dereferencing mistakes.
143 (defmacro define-constant
(name value
&optional doc
)
144 `(defparameter ,name
(if (boundp ',name
) (symbol-value ',name
) ,value
)
145 ,@(when doc
(list doc
))))
147 (define-constant +stat-float-typing
+ 'long-float
)
148 (define-constant +stat-cfloat-typing
+ '(complex long-float
))
149 (define-constant +stat-float-template
+ 0.d0
)
151 ;(defparameter +stat-float-typing+ 'long-float)
152 ;(defparameter +stat-cfloat-typing+ '(complex long-float))
153 ;(defparameter +stat-float-template+ 0.d0)
155 (deftype stat-float
() +stat-float-typing
+)
156 (deftype stat-cfloat
() +stat-cfloat-typing
+)
158 (defparameter machine-epsilon
159 (do ((epsilon (float 1.0 +stat-float-template
+)
161 ((= (+ 1.0 (/ epsilon
2.0)) 1.0) epsilon
)))
163 (defmacro declare-double
(&rest vars
) `(declare (long-float ,@vars
)))
165 (setf *read-default-float-format
* +stat-float-typing
+)
167 ;;; FIX-BASE-DOC adds note about modification to the end of the
168 ;;; documentation string argument.
169 (defmacro fix-base-doc
(doc)
171 "~a~%Modified to coerce arguments(s) to stat-float or stat-cfloat."
174 ;;; FIX-BASE-FUN-DOC fixes documentation of SYM and installs in BASE-SYM
175 (defun fix-base-fun-doc (sym base-sym
)
176 (let ((doc (documentation sym
'function
)))
177 (if doc
(setf (documentation base-sym
'function
) (fix-base-doc doc
)))))
179 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
180 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
182 ;;;; Functions and Macros for modifying functions to coerce to standard
183 ;;;; floating point type.
185 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
186 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
188 ;;; FFIX - coerces its arguments to standard real or complex floating
189 ;;; point number if needed.
190 #-stat-float-is-double-float
193 (coerce ,x
+stat-cfloat-typing
+)
194 (float ,x
+stat-float-template
+)))
196 #+stat-float-is-double-float
197 (defmacro ffix
(x) x
)
199 ;;; MAKEDOUBLE coerces its argument to the standard floating point
200 ;;; type specified by +stat-float-template+
202 (defun makedouble (x) (float x
+stat-float-template
+))
204 ;; Why doesn't this optimization work?
205 ;; #+stat-float-is-double-float
206 ;; (eval-when (compile)
207 ;; (proclaim '(function makedouble (t) long-float)))
210 ;;; MAKE-BASE-TRANS-FUN Macro for re-defining one argument transcendental
213 #-
:stat-float-is-double-float
214 (defmacro make-base-trans-fun
(sym)
215 (let* ((base-sym (intern (string-upcase (format nil
"BASE-~s" sym
))))
216 (doc (documentation sym
'function
))
217 (doc-list (if doc
(list (fix-base-doc doc
)))))
218 `(defun ,base-sym
(x)
220 (declare (inline ,sym coerce float
))
223 #+:stat-float-is-double-float
224 (defmacro make-base-trans-fun
(sym)
225 (let* ((base-sym (intern (string-upcase (format nil
"BASE-~s" sym
))))
226 (doc (documentation sym
'function
)))
227 `(progn (setf (symbol-function ',base-sym
) (symbol-function ',sym
))
228 (if ,doc
(setf (documentation ',base-sym
'function
) ,doc
)))))
231 ;;; MAKE-BASE-TRANS-FUN-2 Macro for re-defining transcendental functions
232 ;;; with an optional second argument
234 #-
:stat-float-is-double-float
235 (defmacro make-base-trans-fun-2
(sym)
236 (let* ((base-sym (intern (string-upcase (format nil
"BASE-~s" sym
))))
237 (doc (documentation sym
'function
))
238 (doc-list (if doc
(list (fix-base-doc doc
)))))
239 `(defun ,base-sym
(x &optional y
)
241 (declare (inline ,sym coerce float
))
242 (if y
(,sym
(ffix x
) (ffix y
)) (,sym
(ffix x
))))))
244 #+:stat-float-is-double-float
245 (defmacro make-base-trans-fun-2
(sym)
246 (let* ((base-sym (intern (string-upcase (format nil
"BASE-~s" sym
))))
247 (doc (documentation sym
'function
)))
248 `(progn (setf (symbol-function ',base-sym
) (symbol-function ',sym
))
249 (if ,doc
(setf (documentation ',base-sym
'function
) ,doc
)))))
251 ;;; Modified base functions to coerce to standard floating point type
256 #-
:stat-float-is-double-float
258 (defun base-float (x &optional
(y +stat-float-template
+)) (float x y
))
259 (fix-base-fun-doc 'float
'base-float
))
261 #+:stat-float-is-double-float
262 (make-base-trans-fun float
)
265 #-
:stat-float-is-double-float
267 (defun base-expt (x y
)
268 (declare (inline expt coerce float integerp
))
269 (if (integerp y
) (expt x y
) (expt (ffix x
) (ffix y
))))
271 (fix-base-fun-doc 'expt
'base-expt
))
273 #+:stat-float-is-double-float
274 (make-base-trans-fun expt
)
277 (make-base-trans-fun-2 log
)
278 (make-base-trans-fun exp
)
279 (make-base-trans-fun sqrt
)
280 (make-base-trans-fun sin
)
281 (make-base-trans-fun cos
)
282 (make-base-trans-fun tan
)
283 (make-base-trans-fun asin
)
284 (make-base-trans-fun acos
)
285 (make-base-trans-fun-2 atan
)
286 (make-base-trans-fun sinh
)
287 (make-base-trans-fun cosh
)
288 (make-base-trans-fun tanh
)
289 (make-base-trans-fun asinh
)
290 (make-base-trans-fun acosh
)
291 (make-base-trans-fun atanh
)
292 (make-base-trans-fun abs
)
293 (make-base-trans-fun phase
)
294 (make-base-trans-fun-2 ffloor
)
295 (make-base-trans-fun-2 fceiling
)
296 (make-base-trans-fun-2 ftruncate
)
297 (make-base-trans-fun-2 fround
)
298 (make-base-trans-fun signum
)
299 (make-base-trans-fun cis
)