1 /* 2 * This file is part of the MicroPython project, http://micropython.org/ 3 * 4 * These math functions are taken from newlib-nano-2, the newlib/libm/math 5 * directory, available from https://github.com/32bitmicro/newlib-nano-2. 6 * 7 * Appropriate copyright headers are reproduced below. 8 */ 9 10 /* kf_sin.c -- float version of k_sin.c 11 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. 12 */ 13 14 /* 15 * ==================================================== 16 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 17 * 18 * Developed at SunPro, a Sun Microsystems, Inc. business. 19 * Permission to use, copy, modify, and distribute this 20 * software is freely granted, provided that this notice 21 * is preserved. 22 * ==================================================== 23 */ 24 25 #include "fdlibm.h" 26 27 #ifdef __STDC__ 28 static const float 29 #else 30 static float 31 #endif 32 half = 5.0000000000e-01f,/* 0x3f000000 */ 33 S1 = -1.6666667163e-01f, /* 0xbe2aaaab */ 34 S2 = 8.3333337680e-03f, /* 0x3c088889 */ 35 S3 = -1.9841270114e-04f, /* 0xb9500d01 */ 36 S4 = 2.7557314297e-06f, /* 0x3638ef1b */ 37 S5 = -2.5050759689e-08f, /* 0xb2d72f34 */ 38 S6 = 1.5896910177e-10f; /* 0x2f2ec9d3 */ 39 40 #ifdef __STDC__ __kernel_sinf(float x,float y,int iy)41 float __kernel_sinf(float x, float y, int iy) 42 #else 43 float __kernel_sinf(x, y, iy) 44 float x,y; int iy; /* iy=0 if y is zero */ 45 #endif 46 { 47 float z,r,v; 48 __int32_t ix; 49 GET_FLOAT_WORD(ix,x); 50 ix &= 0x7fffffff; /* high word of x */ 51 if(ix<0x32000000) /* |x| < 2**-27 */ 52 {if((int)x==0) return x;} /* generate inexact */ 53 z = x*x; 54 v = z*x; 55 r = S2+z*(S3+z*(S4+z*(S5+z*S6))); 56 if(iy==0) return x+v*(S1+z*r); 57 else return x-((z*(half*y-v*r)-y)-v*S1); 58 } 59