/* * IBM Accurate Mathematical Library * written by International Business Machines Corp. * Copyright (C) 2001 Free Software Foundation * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation; either version 2.1 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /********************************************************************/ /* */ /* MODULE_NAME: dosincos.c */ /* */ /* */ /* FUNCTIONS: dubsin */ /* dubcos */ /* docos */ /* FILES NEEDED: endian.h mydefs.h dla.h dosincos.h */ /* sincos.tbl */ /* */ /* Routines compute sin() and cos() as Double-Length numbers */ /********************************************************************/ #include "endian.h" #include "mydefs.h" #include "sincos.tbl" #include "dla.h" #include "dosincos.h" #include "math_private.h" /***********************************************************************/ /* Routine receive Double-Length number (x+dx) and computing sin(x+dx) */ /* as Double-Length number and store it at array v .It computes it by */ /* arithmetic action on Double-Length numbers */ /*(x+dx) between 0 and PI/4 */ /***********************************************************************/ void __dubsin(double x, double dx, double v[]) { double r,s,p,hx,tx,hy,ty,q,c,cc,d,dd,d2,dd2,e,ee, sn,ssn,cs,ccs,ds,dss,dc,dcc; #if 0 double xx,y,yy,z,zz; #endif mynumber u; int4 k; u.x=x+big.x; k = u.i[LOW_HALF]<<2; x=x-(u.x-big.x); d=x+dx; dd=(x-d)+dx; /* sin(x+dx)=sin(Xi+t)=sin(Xi)*cos(t) + cos(Xi)sin(t) where t ->0 */ MUL2(d,dd,d,dd,d2,dd2,p,hx,tx,hy,ty,q,c,cc); sn=sincos.x[k]; /* */ ssn=sincos.x[k+1]; /* sin(Xi) and cos(Xi) */ cs=sincos.x[k+2]; /* */ ccs=sincos.x[k+3]; /* */ MUL2(d2,dd2,s7.x,ss7.x,ds,dss,p,hx,tx,hy,ty,q,c,cc); /* Taylor */ ADD2(ds,dss,s5.x,ss5.x,ds,dss,r,s); MUL2(d2,dd2,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc); /* series */ ADD2(ds,dss,s3.x,ss3.x,ds,dss,r,s); MUL2(d2,dd2,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc); /* for sin */ MUL2(d,dd,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc); ADD2(ds,dss,d,dd,ds,dss,r,s); /* ds=sin(t) */ MUL2(d2,dd2,c8.x,cc8.x,dc,dcc,p,hx,tx,hy,ty,q,c,cc); ;/* Taylor */ ADD2(dc,dcc,c6.x,cc6.x,dc,dcc,r,s); MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc); /* series */ ADD2(dc,dcc,c4.x,cc4.x,dc,dcc,r,s); MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc); /* for cos */ ADD2(dc,dcc,c2.x,cc2.x,dc,dcc,r,s); MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc); /* dc=cos(t) */ MUL2(cs,ccs,ds,dss,e,ee,p,hx,tx,hy,ty,q,c,cc); MUL2(dc,dcc,sn,ssn,dc,dcc,p,hx,tx,hy,ty,q,c,cc); SUB2(e,ee,dc,dcc,e,ee,r,s); ADD2(e,ee,sn,ssn,e,ee,r,s); /* e+ee=sin(x+dx) */ v[0]=e; v[1]=ee; } /**********************************************************************/ /* Routine receive Double-Length number (x+dx) and computes cos(x+dx) */ /* as Double-Length number and store it in array v .It computes it by */ /* arithmetic action on Double-Length numbers */ /*(x+dx) between 0 and PI/4 */ /**********************************************************************/ void __dubcos(double x, double dx, double v[]) { double r,s,p,hx,tx,hy,ty,q,c,cc,d,dd,d2,dd2,e,ee, sn,ssn,cs,ccs,ds,dss,dc,dcc; #if 0 double xx,y,yy,z,zz; #endif mynumber u; int4 k; u.x=x+big.x; k = u.i[LOW_HALF]<<2; x=x-(u.x-big.x); d=x+dx; dd=(x-d)+dx; /* cos(x+dx)=cos(Xi+t)=cos(Xi)cos(t) - sin(Xi)sin(t) */ MUL2(d,dd,d,dd,d2,dd2,p,hx,tx,hy,ty,q,c,cc); sn=sincos.x[k]; /* */ ssn=sincos.x[k+1]; /* sin(Xi) and cos(Xi) */ cs=sincos.x[k+2]; /* */ ccs=sincos.x[k+3]; /* */ MUL2(d2,dd2,s7.x,ss7.x,ds,dss,p,hx,tx,hy,ty,q,c,cc); ADD2(ds,dss,s5.x,ss5.x,ds,dss,r,s); MUL2(d2,dd2,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc); ADD2(ds,dss,s3.x,ss3.x,ds,dss,r,s); MUL2(d2,dd2,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc); MUL2(d,dd,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc); ADD2(ds,dss,d,dd,ds,dss,r,s); MUL2(d2,dd2,c8.x,cc8.x,dc,dcc,p,hx,tx,hy,ty,q,c,cc); ADD2(dc,dcc,c6.x,cc6.x,dc,dcc,r,s); MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc); ADD2(dc,dcc,c4.x,cc4.x,dc,dcc,r,s); MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc); ADD2(dc,dcc,c2.x,cc2.x,dc,dcc,r,s); MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc); MUL2(cs,ccs,ds,dss,e,ee,p,hx,tx,hy,ty,q,c,cc); MUL2(dc,dcc,sn,ssn,dc,dcc,p,hx,tx,hy,ty,q,c,cc); MUL2(d2,dd2,s7.x,ss7.x,ds,dss,p,hx,tx,hy,ty,q,c,cc); ADD2(ds,dss,s5.x,ss5.x,ds,dss,r,s); MUL2(d2,dd2,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc); ADD2(ds,dss,s3.x,ss3.x,ds,dss,r,s); MUL2(d2,dd2,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc); MUL2(d,dd,ds,dss,ds,dss,p,hx,tx,hy,ty,q,c,cc); ADD2(ds,dss,d,dd,ds,dss,r,s); MUL2(d2,dd2,c8.x,cc8.x,dc,dcc,p,hx,tx,hy,ty,q,c,cc); ADD2(dc,dcc,c6.x,cc6.x,dc,dcc,r,s); MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc); ADD2(dc,dcc,c4.x,cc4.x,dc,dcc,r,s); MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc); ADD2(dc,dcc,c2.x,cc2.x,dc,dcc,r,s); MUL2(d2,dd2,dc,dcc,dc,dcc,p,hx,tx,hy,ty,q,c,cc); MUL2(sn,ssn,ds,dss,e,ee,p,hx,tx,hy,ty,q,c,cc); MUL2(dc,dcc,cs,ccs,dc,dcc,p,hx,tx,hy,ty,q,c,cc); ADD2(e,ee,dc,dcc,e,ee,r,s); SUB2(cs,ccs,e,ee,e,ee,r,s); v[0]=e; v[1]=ee; } /**********************************************************************/ /* Routine receive Double-Length number (x+dx) and computes cos(x+dx) */ /* as Double-Length number and store it in array v */ /**********************************************************************/ void __docos(double x, double dx, double v[]) { double y,yy,p,w[2]; if (x>0) {y=x; yy=dx;} else {y=-x; yy=-dx;} if (y<0.5*hp0.x) /* y< PI/4 */ {__dubcos(y,yy,w); v[0]=w[0]; v[1]=w[1];} else if (y<1.5*hp0.x) { /* y< 3/4 * PI */ p=hp0.x-y; /* p = PI/2 - y */ yy=hp1.x-yy; y=p+yy; yy=(p-y)+yy; if (y>0) {__dubsin(y,yy,w); v[0]=w[0]; v[1]=w[1];} /* cos(x) = sin ( 90 - x ) */ else {__dubsin(-y,-yy,w); v[0]=-w[0]; v[1]=-w[1]; } } else { /* y>= 3/4 * PI */ p=2.0*hp0.x-y; /* p = PI- y */ yy=2.0*hp1.x-yy; y=p+yy; yy=(p-y)+yy; __dubcos(y,yy,w); v[0]=-w[0]; v[1]=-w[1]; } }