* 1/sqrt(2) <= x < sqrt(2)
* Theoretical peak relative error = 6.2e-22
*/
-static long double P[] = {
+static const long double P[] = {
4.9962495940332550844739E-1L,
1.0767376367209449010438E1L,
7.7671073698359539859595E1L,
3.4258224542413922935104E2L,
1.0747524399916215149070E2L,
};
-static long double Q[] = {
+static const long double Q[] = {
/* 1.0000000000000000000000E0,*/
2.3479774160285863271658E1L,
1.9444210022760132894510E2L,
* 1/sqrt(2) <= x < sqrt(2)
* Theoretical peak relative error = 6.16e-22
*/
-static long double R[4] = {
+static const long double R[4] = {
1.9757429581415468984296E-3L,
-7.1990767473014147232598E-1L,
1.0777257190312272158094E1L,
-3.5717684488096787370998E1L,
};
-static long double S[4] = {
+static const long double S[4] = {
/* 1.00000000000000000000E0L,*/
-2.6201045551331104417768E1L,
1.9361891836232102174846E2L,
return x;
if (x == INFINITY)
return x;
- if (x <= 0.0L) {
- if (x == 0.0L)
+ if (x <= 0.0) {
+ if (x == 0.0)
return -INFINITY;
return NAN;
}
if (e > 2 || e < -2) {
if (x < SQRTH) { /* 2(2x-1)/(2x+1) */
e -= 1;
- z = x - 0.5L;
- y = 0.5L * z + 0.5L;
+ z = x - 0.5;
+ y = 0.5 * z + 0.5;
} else { /* 2 (x-1)/(x+1) */
- z = x - 0.5L;
- z -= 0.5L;
- y = 0.5L * x + 0.5L;
+ z = x - 0.5;
+ z -= 0.5;
+ y = 0.5 * x + 0.5;
}
x = z / y;
z = x*x;
/* logarithm using log(1+x) = x - .5x**2 + x**3 P(x)/Q(x) */
if (x < SQRTH) {
e -= 1;
- x = ldexpl(x, 1) - 1.0L; /* 2x - 1 */
+ x = 2.0*x - 1.0;
} else {
- x = x - 1.0L;
+ x = x - 1.0;
}
z = x*x;
y = x * (z * __polevll(x, P, 6) / __p1evll(x, Q, 7));
- y = y - ldexpl(z, -1); /* -0.5x^2 + ... */
+ y = y - 0.5*z;
done:
/* Multiply log of fraction by log2(e)