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authornsz <nsz@port70.net>2012-03-19 23:41:19 +0100
committernsz <nsz@port70.net>2012-03-19 23:41:19 +0100
commit0cbb65479147ecdaa664e88cc2a5a925f3de502f (patch)
tree7b6dc53fcec6497d55746d3cc47f167a20b7aa57 /src/math/erff.c
parentb03255af77776703c8d48819e824d09f6f54ba86 (diff)
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code cleanup of named constants
zero, one, two, half are replaced by const literals The policy was to use the f suffix for float consts (1.0f), but don't use suffix for long double consts (these consts can be exactly represented as double).
Diffstat (limited to 'src/math/erff.c')
-rw-r--r--src/math/erff.c57
1 files changed, 27 insertions, 30 deletions
diff --git a/src/math/erff.c b/src/math/erff.c
index eef4851e..a0a304e5 100644
--- a/src/math/erff.c
+++ b/src/math/erff.c
@@ -17,9 +17,6 @@
static const float
tiny = 1e-30,
-half = 5.0000000000e-01, /* 0x3F000000 */
-one = 1.0000000000e+00, /* 0x3F800000 */
-two = 2.0000000000e+00, /* 0x40000000 */
/* c = (subfloat)0.84506291151 */
erx = 8.4506291151e-01, /* 0x3f58560b */
/*
@@ -100,7 +97,7 @@ float erff(float x)
if (ix >= 0x7f800000) {
/* erf(nan)=nan, erf(+-inf)=+-1 */
i = ((uint32_t)hx>>31)<<1;
- return (float)(1-i)+one/x;
+ return (float)(1-i)+1.0f/x;
}
if (ix < 0x3f580000) { /* |x| < 0.84375 */
if (ix < 0x31800000) { /* |x| < 2**-28 */
@@ -111,42 +108,42 @@ float erff(float x)
}
z = x*x;
r = pp0+z*(pp1+z*(pp2+z*(pp3+z*pp4)));
- s = one+z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5))));
+ s = 1.0f+z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5))));
y = r/s;
return x + x*y;
}
if (ix < 0x3fa00000) { /* 0.84375 <= |x| < 1.25 */
- s = fabsf(x)-one;
+ s = fabsf(x)-1.0f;
P = pa0+s*(pa1+s*(pa2+s*(pa3+s*(pa4+s*(pa5+s*pa6)))));
- Q = one+s*(qa1+s*(qa2+s*(qa3+s*(qa4+s*(qa5+s*qa6)))));
+ Q = 1.0f+s*(qa1+s*(qa2+s*(qa3+s*(qa4+s*(qa5+s*qa6)))));
if (hx >= 0)
return erx + P/Q;
return -erx - P/Q;
}
if (ix >= 0x40c00000) { /* inf > |x| >= 6 */
if (hx >= 0)
- return one - tiny;
- return tiny - one;
+ return 1.0f - tiny;
+ return tiny - 1.0f;
}
x = fabsf(x);
- s = one/(x*x);
+ s = 1.0f/(x*x);
if (ix < 0x4036DB6E) { /* |x| < 1/0.35 */
R = ra0+s*(ra1+s*(ra2+s*(ra3+s*(ra4+s*(
ra5+s*(ra6+s*ra7))))));
- S = one+s*(sa1+s*(sa2+s*(sa3+s*(sa4+s*(
+ S = 1.0f+s*(sa1+s*(sa2+s*(sa3+s*(sa4+s*(
sa5+s*(sa6+s*(sa7+s*sa8)))))));
} else { /* |x| >= 1/0.35 */
R = rb0+s*(rb1+s*(rb2+s*(rb3+s*(rb4+s*(
rb5+s*rb6)))));
- S = one+s*(sb1+s*(sb2+s*(sb3+s*(sb4+s*(
+ S = 1.0f+s*(sb1+s*(sb2+s*(sb3+s*(sb4+s*(
sb5+s*(sb6+s*sb7))))));
}
GET_FLOAT_WORD(ix, x);
SET_FLOAT_WORD(z, ix&0xfffff000);
r = expf(-z*z - 0.5625f) * expf((z-x)*(z+x) + R/S);
if (hx >= 0)
- return one - r/x;
- return r/x - one;
+ return 1.0f - r/x;
+ return r/x - 1.0f;
}
float erfcf(float x)
@@ -158,50 +155,50 @@ float erfcf(float x)
ix = hx & 0x7fffffff;
if (ix >= 0x7f800000) {
/* erfc(nan)=nan, erfc(+-inf)=0,2 */
- return (float)(((uint32_t)hx>>31)<<1) + one/x;
+ return (float)(((uint32_t)hx>>31)<<1) + 1.0f/x;
}
if (ix < 0x3f580000) { /* |x| < 0.84375 */
if (ix < 0x23800000) /* |x| < 2**-56 */
- return one - x;
+ return 1.0f - x;
z = x*x;
r = pp0+z*(pp1+z*(pp2+z*(pp3+z*pp4)));
- s = one+z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5))));
+ s = 1.0f+z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5))));
y = r/s;
if (hx < 0x3e800000) { /* x<1/4 */
- return one - (x+x*y);
+ return 1.0f - (x+x*y);
} else {
r = x*y;
- r += (x-half);
- return half - r ;
+ r += (x-0.5f);
+ return 0.5f - r ;
}
}
if (ix < 0x3fa00000) { /* 0.84375 <= |x| < 1.25 */
- s = fabsf(x)-one;
+ s = fabsf(x)-1.0f;
P = pa0+s*(pa1+s*(pa2+s*(pa3+s*(pa4+s*(pa5+s*pa6)))));
- Q = one+s*(qa1+s*(qa2+s*(qa3+s*(qa4+s*(qa5+s*qa6)))));
+ Q = 1.0f+s*(qa1+s*(qa2+s*(qa3+s*(qa4+s*(qa5+s*qa6)))));
if(hx >= 0) {
- z = one - erx;
+ z = 1.0f - erx;
return z - P/Q;
} else {
z = erx + P/Q;
- return one + z;
+ return 1.0f + z;
}
}
if (ix < 0x41e00000) { /* |x| < 28 */
x = fabsf(x);
- s = one/(x*x);
+ s = 1.0f/(x*x);
if (ix < 0x4036DB6D) { /* |x| < 1/.35 ~ 2.857143*/
R = ra0+s*(ra1+s*(ra2+s*(ra3+s*(ra4+s*(
ra5+s*(ra6+s*ra7))))));
- S = one+s*(sa1+s*(sa2+s*(sa3+s*(sa4+s*(
+ S = 1.0f+s*(sa1+s*(sa2+s*(sa3+s*(sa4+s*(
sa5+s*(sa6+s*(sa7+s*sa8)))))));
} else { /* |x| >= 1/.35 ~ 2.857143 */
if (hx < 0 && ix >= 0x40c00000) /* x < -6 */
- return two-tiny;
+ return 2.0f-tiny;
R = rb0+s*(rb1+s*(rb2+s*(rb3+s*(rb4+s*(
rb5+s*rb6)))));
- S = one+s*(sb1+s*(sb2+s*(sb3+s*(sb4+s*(
+ S = 1.0f+s*(sb1+s*(sb2+s*(sb3+s*(sb4+s*(
sb5+s*(sb6+s*sb7))))));
}
GET_FLOAT_WORD(ix, x);
@@ -209,9 +206,9 @@ float erfcf(float x)
r = expf(-z*z - 0.5625f) * expf((z-x)*(z+x) + R/S);
if (hx > 0)
return r/x;
- return two - r/x;
+ return 2.0f - r/x;
}
if (hx > 0)
return tiny*tiny;
- return two - tiny;
+ return 2.0f - tiny;
}