use radix literals

[factor.git] / basis / math / functions / functions.factor

diff --git a/basis/math/functions/functions.factor b/basis/math/functions/functions.factor
index 1b120831c0355d3ff2138c68215b629b77ded4df..f1e68c9f86efd6ddc00aac19d8bd8f1898725900 100644 (file)
--- a/basis/math/functions/functions.factor
+++ b/basis/math/functions/functions.factor
@@ -94,7 +94,7 @@ M: complex exp >rect [ exp ] dip polar> ; inline
         2nip
     ] [
         swap [ /mod [ over * swapd - ] dip ] keep (gcd)
-    ] if ;
+    ] if ; inline recursive
 
 PRIVATE>
 
@@ -109,13 +109,13 @@ PRIVATE>
 : nth-root ( n x -- y ) swap recip ^ ; inline
 
 : gcd ( x y -- a d )
-    [ 0 1 ] 2dip (gcd) dup 0 < [ neg ] when ; foldable
+    [ 0 1 ] 2dip (gcd) dup 0 < [ neg ] when ; inline
 
 : lcm ( a b -- c )
     [ * ] 2keep gcd nip /i ; foldable
 
 : divisor? ( m n -- ? )
-    mod 0 = ;
+    mod 0 = ; inline
 
 ERROR: non-trivial-divisor n ;
 
@@ -155,6 +155,23 @@ M: real absq sq ; inline
 : >=1? ( x -- ? )
     dup complex? [ drop f ] [ 1 >= ] if ; inline
 
+GENERIC: frexp ( x -- y exp )
+
+M: float frexp
+    dup fp-special? [ dup zero? ] unless* [ 0 ] [
+        double>bits
+        [ 0x800f,ffff,ffff,ffff bitand 0.5 double>bits bitor bits>double ]
+        [ -52 shift 0x7ff bitand 1022 - ] bi
+    ] if ; inline
+
+M: integer frexp
+    [ 0.0 0 ] [
+        dup 0 > [ 1 ] [ abs -1 ] if swap dup log2 [
+            52 swap - shift 0x000f,ffff,ffff,ffff bitand
+            0.5 double>bits bitor bits>double
+        ] [ 1 + ] bi [ * ] dip
+    ] if-zero ; inline
+
 GENERIC: log ( x -- y )
 
 M: float log dup 0.0 >= [ flog ] [ 0.0 rect> log ] if ; inline
@@ -163,6 +180,29 @@ M: real log >float log ; inline
 
 M: complex log >polar [ flog ] dip rect> ; inline
 
+<PRIVATE
+
+: most-negative-finite-float ( -- x )
+    -0x1.ffff,ffff,ffff,fp1023 >integer ; inline
+: most-positive-finite-float ( -- x )
+    0x1.ffff,ffff,ffff,fp1023 >integer ; inline
+CONSTANT: log-2   0x1.62e42fefa39efp-1
+CONSTANT: log10-2 0x1.34413509f79ffp-2
+
+: (representable-as-float?) ( x -- ? )
+    most-negative-finite-float
+    most-positive-finite-float between? ; inline
+
+: (bignum-log) ( n log-quot: ( x -- y ) log-2 -- log )
+    [ dup ] dip '[
+        dup (representable-as-float?)
+        [ >float @ ] [ frexp [ @ ] [ _ * ] bi* + ] if
+    ] call ; inline
+
+PRIVATE>
+
+M: bignum log [ log ] log-2 (bignum-log) ;
+
 GENERIC: log1+ ( x -- y )
 
 M: object log1+ 1 + log ; inline
@@ -177,6 +217,8 @@ M: real log10 >float flog10 ; inline
 
 M: complex log10 log 10 log / ; inline
 
+M: bignum log10 [ log10 ] log10-2 (bignum-log) ;
+
 GENERIC: cos ( x -- y ) foldable
 
 M: complex cos