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Ambiguity of BigDecimal::limit removed.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@4381 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
This commit is contained in:
shigek
parent
3d7147bcea
commit
0b6cf4bea8
5 changed files with 97 additions and 70 deletions
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@ -1,3 +1,7 @@
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Wed Aug 13 23:31:00 2003 Shigeo Kobayashi <shigek@ruby-lang.org>
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* ext/bigdecimal.c .h .html: Ambiguity of BigDecimal::limit removed.
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Wed Aug 13 19:21:34 2003 Christian Neukirchen <chneukirchen@yahoo.de>
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* lib/webrick/https.rb (HTTPServer#run): should set syncing-mode
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@ -8,26 +8,8 @@
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* License or the Artistic License, as specified in the README file
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* of this BigDecimal distribution.
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*
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* NOTES:
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* For the notes other than listed bellow,see ruby CVS log.
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* 2003-04-17
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* Bug in negative.exp(n) reported by Hitoshi Miyazaki fixed.
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* 2003-03-28
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* V1.0 checked in to CVS(ruby/ext/bigdecimal).
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* use rb_str2cstr() instead of STR2CSTR().
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* 2003-01-03
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* assign instead of asign(by knu),use string.h functions(by t.saito).
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* 2002-12-06
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* The sqrt() bug reported by Bret Jolly fixed.
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* 2002-5-6
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* The bug reported by Sako Hiroshi (ruby-list:34988) in to_i fixed.
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* 2002-4-17
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* methods prec and double_fig(class method) added(S.K).
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* 2002-04-04
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* Copied from BigFloat 1.1.9 and
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* hash method changed according to the suggestion from Akinori MUSHA <knu@iDaemons.org>.
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* All ! class methods deactivated(but not actually removed).
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* to_s and to_s2 merged to one to_s[(n)].
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* NOTE: Change log in this source removed to reduce source code size.
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* See rev. 1.25 if needed.
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*
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*/
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@ -74,7 +56,8 @@ BigDecimal_version(VALUE self)
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*/
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static unsigned short VpGetException(void);
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static void VpSetException(unsigned short f);
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static int VpInternalRound(Real *c,int ixDigit,U_LONG vPrev,U_LONG v);
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static void VpInternalRound(Real *c,int ixDigit,U_LONG vPrev,U_LONG v);
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static int VpLimitRound(Real *c,U_LONG ixDigit);
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/*
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* **** BigDecimal part ****
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@ -229,10 +212,15 @@ BigDecimal_load(VALUE self, VALUE str)
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}
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static VALUE
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BigDecimal_mode(VALUE self, VALUE which, VALUE val)
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BigDecimal_mode(int argc, VALUE *argv, VALUE self)
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{
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VALUE which;
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VALUE val;
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int na;
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unsigned long f,fo;
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if(rb_scan_args(argc,argv,"11",&which,&val)==1) val = Qnil;
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Check_Type(which, T_FIXNUM);
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f = (unsigned long)FIX2INT(which);
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@ -658,7 +646,7 @@ BigDecimal_div(VALUE self, VALUE r)
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r 00000yyyyy ==> (y/b)*BASE >= HALF_BASE
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*/
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/* Round */
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if(VpIsDef(c) && (!VpIsZero(c))) {
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if(div->frac[0]) { /* frac[0] must be zero for NaN,INF,Zero */
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VpInternalRound(c,0,c->frac[c->Prec-1],(VpBaseVal()*res->frac[0])/div->frac[0]);
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}
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return ToValue(c);
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@ -816,12 +804,14 @@ BigDecimal_div2(int argc, VALUE *argv, VALUE self)
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Real *av=NULL, *bv=NULL, *cv=NULL;
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U_LONG ix = (U_LONG)GetPositiveInt(n);
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U_LONG mx = (ix+VpBaseFig()*2);
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U_LONG pl = VpSetPrecLimit(0);
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GUARD_OBJ(cv,VpCreateRbObject(mx,"0"));
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GUARD_OBJ(av,GetVpValue(self,1));
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GUARD_OBJ(bv,GetVpValue(b,1));
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mx = cv->MaxPrec+1;
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GUARD_OBJ(res,VpCreateRbObject((mx * 2 + 2)*VpBaseFig(), "#0"));
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VpDivd(cv,res,av,bv);
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VpSetPrecLimit(pl);
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VpLeftRound(cv,VpGetRoundMode(),ix);
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return ToValue(cv);
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}
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@ -833,7 +823,9 @@ BigDecimal_add2(VALUE self, VALUE b, VALUE n)
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ENTER(2);
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Real *cv;
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U_LONG mx = (U_LONG)GetPositiveInt(n);
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U_LONG pl = VpSetPrecLimit(0);
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VALUE c = BigDecimal_add(self,b);
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VpSetPrecLimit(pl);
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GUARD_OBJ(cv,GetVpValue(c,1));
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VpLeftRound(cv,VpGetRoundMode(),mx);
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return ToValue(cv);
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@ -845,7 +837,9 @@ BigDecimal_sub2(VALUE self, VALUE b, VALUE n)
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ENTER(2);
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Real *cv;
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U_LONG mx = (U_LONG)GetPositiveInt(n);
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U_LONG pl = VpSetPrecLimit(0);
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VALUE c = BigDecimal_sub(self,b);
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VpSetPrecLimit(pl);
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GUARD_OBJ(cv,GetVpValue(c,1));
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VpLeftRound(cv,VpGetRoundMode(),mx);
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return ToValue(cv);
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@ -857,7 +851,9 @@ BigDecimal_mult2(VALUE self, VALUE b, VALUE n)
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ENTER(2);
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Real *cv;
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U_LONG mx = (U_LONG)GetPositiveInt(n);
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U_LONG pl = VpSetPrecLimit(0);
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VALUE c = BigDecimal_mult(self,b);
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VpSetPrecLimit(pl);
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GUARD_OBJ(cv,GetVpValue(c,1));
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VpLeftRound(cv,VpGetRoundMode(),mx);
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return ToValue(cv);
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@ -919,6 +915,7 @@ BigDecimal_round(int argc, VALUE *argv, VALUE self)
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U_LONG mx;
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VALUE vLoc;
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VALUE vRound;
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U_LONG pl;
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int sw = VpGetRoundMode();
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@ -943,9 +940,11 @@ BigDecimal_round(int argc, VALUE *argv, VALUE self)
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break;
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}
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pl = VpSetPrecLimit(0);
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GUARD_OBJ(a,GetVpValue(self,1));
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mx = a->Prec *(VpBaseFig() + 1);
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GUARD_OBJ(c,VpCreateRbObject(mx, "0"));
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VpSetPrecLimit(pl);
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VpActiveRound(c,a,sw,iLoc);
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return ToValue(c);
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}
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@ -958,6 +957,7 @@ BigDecimal_truncate(int argc, VALUE *argv, VALUE self)
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int iLoc;
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U_LONG mx;
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VALUE vLoc;
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U_LONG pl = VpSetPrecLimit(0);
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if(rb_scan_args(argc,argv,"01",&vLoc)==0) {
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iLoc = 0;
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@ -969,6 +969,7 @@ BigDecimal_truncate(int argc, VALUE *argv, VALUE self)
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GUARD_OBJ(a,GetVpValue(self,1));
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mx = a->Prec *(VpBaseFig() + 1);
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GUARD_OBJ(c,VpCreateRbObject(mx, "0"));
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VpSetPrecLimit(pl);
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VpActiveRound(c,a,VP_ROUND_DOWN,iLoc); /* 0: truncate */
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return ToValue(c);
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}
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@ -995,6 +996,7 @@ BigDecimal_floor(int argc, VALUE *argv, VALUE self)
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U_LONG mx;
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int iLoc;
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VALUE vLoc;
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U_LONG pl = VpSetPrecLimit(0);
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if(rb_scan_args(argc,argv,"01",&vLoc)==0) {
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iLoc = 0;
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@ -1006,6 +1008,7 @@ BigDecimal_floor(int argc, VALUE *argv, VALUE self)
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GUARD_OBJ(a,GetVpValue(self,1));
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mx = a->Prec *(VpBaseFig() + 1);
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GUARD_OBJ(c,VpCreateRbObject(mx, "0"));
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VpSetPrecLimit(pl);
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VpActiveRound(c,a,VP_ROUND_FLOOR,iLoc);
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return ToValue(c);
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}
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@ -1018,6 +1021,7 @@ BigDecimal_ceil(int argc, VALUE *argv, VALUE self)
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U_LONG mx;
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int iLoc;
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VALUE vLoc;
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U_LONG pl = VpSetPrecLimit(0);
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if(rb_scan_args(argc,argv,"01",&vLoc)==0) {
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iLoc = 0;
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@ -1029,6 +1033,7 @@ BigDecimal_ceil(int argc, VALUE *argv, VALUE self)
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GUARD_OBJ(a,GetVpValue(self,1));
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mx = a->Prec *(VpBaseFig() + 1);
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GUARD_OBJ(c,VpCreateRbObject(mx, "0"));
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VpSetPrecLimit(pl);
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VpActiveRound(c,a,VP_ROUND_CEIL,iLoc);
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return ToValue(c);
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}
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@ -1205,8 +1210,14 @@ BigDecimal_limit(int argc, VALUE *argv, VALUE self)
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VALUE nCur = INT2NUM(VpGetPrecLimit());
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if(rb_scan_args(argc,argv,"01",&nFig)==1) {
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int nf;
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if(nFig==Qnil) return nCur;
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Check_Type(nFig, T_FIXNUM);
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VpSetPrecLimit(FIX2INT(nFig));
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nf = FIX2INT(nFig);
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if(nf<0) {
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rb_raise(rb_eArgError, "argument must be positive");
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}
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VpSetPrecLimit(nf);
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}
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return nCur;
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}
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@ -1298,7 +1309,7 @@ Init_bigdecimal(void)
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/* Class methods */
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rb_define_singleton_method(rb_cBigDecimal, "new", BigDecimal_new, -1);
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rb_define_singleton_method(rb_cBigDecimal, "mode", BigDecimal_mode, 2);
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rb_define_singleton_method(rb_cBigDecimal, "mode", BigDecimal_mode, -1);
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rb_define_singleton_method(rb_cBigDecimal, "limit", BigDecimal_limit, -1);
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rb_define_singleton_method(rb_cBigDecimal, "double_fig", BigDecimal_double_fig, 0);
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rb_define_singleton_method(rb_cBigDecimal, "induced_from",BigDecimal_induced_from, 1);
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@ -2057,7 +2068,7 @@ VpAsgn(Real *c, Real *a, int isw)
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return 0;
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}
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if(VpIsInf(a)) {
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VpSetInf(c,isw);
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VpSetInf(c,isw*VpGetSign(a));
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return 0;
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}
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@ -2069,8 +2080,13 @@ VpAsgn(Real *c, Real *a, int isw)
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c->Prec = n;
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memcpy(c->frac, a->frac, n * sizeof(U_LONG));
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/* Needs round ? */
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if(c->Prec < a->Prec) {
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VpInternalRound(c,n,(n>0)?a->frac[n-1]:0,a->frac[n]);
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if(isw!=10) {
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/* Not in ActiveRound */
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if(c->Prec < a->Prec) {
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VpInternalRound(c,n,(n>0)?a->frac[n-1]:0,a->frac[n]);
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} else {
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VpLimitRound(c,0);
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}
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}
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} else {
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/* The value of 'a' is zero. */
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@ -2292,8 +2308,7 @@ VpAddAbs(Real *a, Real *b, Real *c)
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}
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}
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if(c_pos) c->frac[c_pos - 1] += carry;
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if(!VpInternalRound(c,0,(c->Prec>0)?a->frac[c->Prec-1]:0,mrv)) VpNmlz(c);
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VpInternalRound(c,0,(c->Prec>0)?a->frac[c->Prec-1]:0,mrv);
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goto Exit;
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Assign_a:
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@ -2406,8 +2421,7 @@ VpSubAbs(Real *a, Real *b, Real *c)
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}
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}
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if(c_pos) c->frac[c_pos - 1] -= borrow;
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if(!VpInternalRound(c,0,(c->Prec>0)?a->frac[c->Prec-1]:0,mrv)) VpNmlz(c);
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VpInternalRound(c,0,(c->Prec>0)?a->frac[c->Prec-1]:0,mrv);
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goto Exit;
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Assign_a:
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@ -3128,8 +3142,7 @@ VpExponent10(Real *a)
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S_LONG ex;
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U_LONG n;
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if(!VpIsDef(a)) return 0;
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if(VpIsZero(a)) return 0;
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if(!VpHasVal(a)) return 0;
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ex =(a->exponent) * BASE_FIG;
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n = BASE1;
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@ -3564,8 +3577,8 @@ VpDtoV(Real *m, double d)
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m->Prec = ind_m + 1;
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m->exponent = ne;
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if(!VpInternalRound(m,0,(m->Prec>0)?m->frac[m->Prec-1]:0,
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(U_LONG)(val*((double)((S_INT)BASE))))) VpNmlz(m);
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VpInternalRound(m,0,(m->Prec>0)?m->frac[m->Prec-1]:0,
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(U_LONG)(val*((double)((S_INT)BASE))));
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Exit:
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#ifdef _DEBUG
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@ -3653,19 +3666,14 @@ VpSqrt(Real *y, Real *x)
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S_LONG nr;
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double val;
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if(!VpIsDef(x)) {
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if(!VpHasVal(x)) {
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VpAsgn(y,x,1);
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goto Exit;
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}
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if(VpIsZero(x)) {
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VpSetZero(y,VpGetSign(x));
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goto Exit;
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}
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if(VpGetSign(x) < 0) {
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VpSetZero(y,VpGetSign(x));
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return VpException(VP_EXCEPTION_OP,"(VpSqrt) SQRT(negative valuw)",0);
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VpSetNaN(y);
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return VpException(VP_EXCEPTION_OP,"(VpSqrt) SQRT(negative value)",0);
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}
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n = (S_LONG)y->MaxPrec;
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@ -3769,7 +3777,6 @@ VpMidRound(Real *y, int f, int nf)
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if(ix<0 || ((U_LONG)ix)>=y->Prec) return; /* Unable to round */
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ioffset = nf - ix*((int)BASE_FIG);
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memset(y->frac+ix+1, 0, (y->Prec - (ix+1)) * sizeof(U_LONG));
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/* VpNmlz(y); */
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v = y->frac[ix];
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/* drop digits after pointed digit */
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n = BASE_FIG - ioffset - 1;
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@ -3830,8 +3837,7 @@ VpLeftRound(Real *y, int f, int nf)
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{
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U_LONG v;
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if(!VpIsDef(y)) return; /* Unable to round */
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if(VpIsZero(y)) return;
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if(!VpHasVal(y)) return; /* Unable to round */
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v = y->frac[0];
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nf -= VpExponent(y)*BASE_FIG;
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@ -3844,19 +3850,31 @@ VP_EXPORT void
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VpActiveRound(Real *y, Real *x, int f, int nf)
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{
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/* First,assign whole value in truncation mode */
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VpAsgn(y, x, 1); /* 1 round off,2 round up */
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if(!VpIsDef(y)) return; /* Unable to round */
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if(VpIsZero(y)) return;
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if(VpAsgn(y, x, 10)<=1) return; /* Zero,NaN,or Infinity */
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VpMidRound(y,f,nf);
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}
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static int
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static int
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VpLimitRound(Real *c,U_LONG ixDigit)
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{
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U_LONG ix = VpGetPrecLimit();
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if(!ix) return 0;
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if(!ixDigit) ixDigit = c->Prec;
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if((ix+BASE_FIG-1)/BASE_FIG >= ixDigit) return 0;
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VpLeftRound(c,VpGetRoundMode(),ix);
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return 1;
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}
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static void
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VpInternalRound(Real *c,int ixDigit,U_LONG vPrev,U_LONG v)
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{
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int f = 0;
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if(!VpIsDef(c)) return f; /* Unable to round */
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if(VpIsZero(c)) return f;
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VpNmlz(c);
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if(!VpHasVal(c)) return; /* Unable to round */
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if(VpLimitRound(c,ixDigit)) return;
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v /= BASE1;
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switch(gfRoundMode) {
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@ -3882,8 +3900,10 @@ VpInternalRound(Real *c,int ixDigit,U_LONG vPrev,U_LONG v)
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else if(v==5 && vPrev%2) f = 1;
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break;
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}
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if(f) VpRdup(c,ixDigit); /* round up */
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return f;
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if(f) {
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VpRdup(c,ixDigit); /* round up */
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VpNmlz(c);
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}
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}
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/*
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|
@ -3919,7 +3939,7 @@ VpFrac(Real *y, Real *x)
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{
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U_LONG my, ind_y, ind_x;
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|
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if(!VpIsDef(x) || VpIsZero(x)) {
|
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if(!VpHasVal(x)) {
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VpAsgn(y,x,1);
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goto Exit;
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}
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|
|
|
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|
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@ -208,6 +208,7 @@ VP_EXPORT void VpSinCos(Real *psin,Real *pcos,Real *x);
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#define VpSetPosInf(a) ((a)->frac[0]=0,(a)->Prec=1,(a)->sign=VP_SIGN_POSITIVE_INFINITE)
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#define VpSetNegInf(a) ((a)->frac[0]=0,(a)->Prec=1,(a)->sign=VP_SIGN_NEGATIVE_INFINITE)
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#define VpSetInf(a,s) ( ((s)>0)?VpSetPosInf(a):VpSetNegInf(a) )
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#define VpHasVal(a) (a->frac[0])
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#define VpIsOne(a) ((a->Prec==1)&&(a->frac[0]==1)&&(a->exponent==1))
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#define VpExponent(a) (a->exponent)
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#ifdef _DEBUG
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|
|
|||
|
|
@ -118,7 +118,10 @@ but the resulting digits obtained may differ in future version.
|
|||
</BLOCKQUOTE>
|
||||
|
||||
<LI><B>mode</B></LI><BLOCKQUOTE>
|
||||
mode method controls BigDecimal computation.Following usage are defined.<BR>
|
||||
f = BigDecimal.mode(s[,v])<BR>
|
||||
mode method controls BigDecimal computation. If the second argument is not given or is nil,then the value
|
||||
of current setting is returned.
|
||||
Following usage are defined.<BR>
|
||||
<P><B>[EXCEPTION control]</B><P>
|
||||
Actions when computation results NaN or Infinity can be defined as follows.
|
||||
<P>
|
||||
|
|
@ -175,13 +178,12 @@ use truncate/round/ceil/floor/add/sub/mult/div mthods for each instance instead.
|
|||
</BLOCKQUOTE>
|
||||
|
||||
<LI><B>limit[(n)]</B></LI><BLOCKQUOTE>
|
||||
Limits the maximum digits that the newly created BigDecimal objects can hold
|
||||
never exceed n+? (Currently,? can not be determined beforehand,but not so big).
|
||||
Limits the maximum digits that the newly created BigDecimal objects can hold never exceed n.
|
||||
This means the rounding operation specified by BigDecimal.mode is
|
||||
performed if necessary.
|
||||
limit returns maximum value before set.
|
||||
limit returns the value before set if n is nil or is not specified.
|
||||
Zero,the default value,means no upper limit.<BR>
|
||||
Except for zero,the limit has more priority than instance methods such as truncate,round,ceil,floor,add,sub,mult,and div. <BR>
|
||||
The limit has no more priority than instance methods such as truncate,round,ceil,floor,add,sub,mult,and div. <BR>
|
||||
mf = BigDecimal::limit(n)<BR>
|
||||
</BLOCKQUOTE>
|
||||
|
||||
|
|
|
|||
|
|
@ -126,7 +126,10 @@ BigDecimal("1",10) / BigDecimal("3",10) # => 0.3333333333 3333333333 33333333E0
|
|||
</BLOCKQUOTE>
|
||||
|
||||
<LI><B>mode</B></LI><BLOCKQUOTE>
|
||||
BigDecimalの実行結果を制御します。以下の使用方法が定義されています。
|
||||
f = BigDecimal.mode(s[,v])<BR>
|
||||
BigDecimalの実行結果を制御します。第２引数を省略、または nil を指定すると
|
||||
現状の設定値が戻ります。<BR>
|
||||
以下の使用方法が定義されています。
|
||||
<P>
|
||||
<B>[例外処理]</B><P>
|
||||
計算結果が非数(NaN)やゼロによる除算になったときの処理を定義することができます。
|
||||
|
|
@ -159,8 +162,7 @@ EXCEPTION_INFINITY
|
|||
は今のところ同じです。<BR>
|
||||
戻り値は、設定後の値です。「値」の意味は、例えば
|
||||
BigDecimal::EXCEPTION_NaNと「値」の & が ゼロ以外ならば
|
||||
EXCEPTION_NaNが設定されているという意味です。<BR>
|
||||
第２引数に nil を指定すると、現状の設定値が返ります。
|
||||
EXCEPTION_NaNが設定されているという意味です。
|
||||
|
||||
<P>
|
||||
<B>[丸め処理指定]</B><P>
|
||||
|
|
@ -183,20 +185,18 @@ f = BigDecimal::mode(BigDecimal::ROUND_MODE,flag)
|
|||
戻り値は指定後の flag の値です。
|
||||
第２引数に nil を指定すると、現状の設定値が返ります。
|
||||
mode メソッドでは丸め操作の位置をユーザが指定することはできません。
|
||||
丸め操作と位置を自分で制御したい場合は truncate/round/ceil/floor や
|
||||
丸め操作と位置を自分で制御したい場合は BigDecimal::limit や truncate/round/ceil/floor、
|
||||
add/sub/mult/div といったインスタンスメソッドを使用して下さい。
|
||||
</BLOCKQUOTE>
|
||||
<LI><B>limit([n])</B></LI><BLOCKQUOTE>
|
||||
生成されるBigDecimalオブジェクトの最大桁数をn桁に制限します。
|
||||
戻り値は設定する前の値です。設定値のデフォルト値は０で、桁数無制限という意味です。
|
||||
n を指定しない場合は、現状の最大桁数が返ります。<BR>
|
||||
n を指定しない、または n が nil の場合は、現状の最大桁数が返ります。<BR>
|
||||
計算を続行する間に、数字の桁数が無制限に増えてしまうような場合
|
||||
limit で予め桁数を制限できます。この場合 BigDecimal.mode で指定された
|
||||
丸め処理が実行されます。
|
||||
ただし、実際には n より若干大きい
|
||||
桁数が確保されます。また、limit による桁数制限は(無制限を除いて)、
|
||||
インスタンスメソッド (truncate/round/ceil/floor/add/sub/mult/div) より
|
||||
優先されるので注意が必要です。<BR>
|
||||
ただし、インスタンスメソッド (truncate/round/ceil/floor/add/sub/mult/div) の
|
||||
桁数制限は limit より優先されます。<BR>
|
||||
mf = BigDecimal::limit(n)<BR>
|
||||
</BLOCKQUOTE>
|
||||
|
||||
|
|
|
|||
Loading…
Reference in a new issue