ref: bc7b9cf7c49595c758d68c30ee1179740e269121
parent: f6e3a00fc29a7770b39c1ad51e4cfbff305bda38
author: S. Gilles <sgilles@math.umd.edu>
date: Thu Jun 28 06:33:47 EDT 2018
Fix pi/2 constants.
--- a/lib/math/ancillary/pi-constants.c
+++ b/lib/math/ancillary/pi-constants.c
@@ -48,9 +48,10 @@
printf("\n");
printf("1000 bits of pi/2:\n");
+ mpfr_const_pi(pi, MPFR_RNDN);
+ mpfr_div_si(pi, pi, 2, MPFR_RNDN);
for (int bits_obtained = 0; bits_obtained < 1000; bits_obtained += 53) {
- mpfr_div_si(pi, pi, 2, MPFR_RNDN);
d = mpfr_get_d(pi, MPFR_RNDN);
u = FLT64_TO_UINT64(d);
printf("%#018lx\n", u);
@@ -66,7 +67,6 @@
d = mpfr_get_d(pi, MPFR_RNDN);
u = FLT64_TO_UINT64(d);
printf("%#018lx\n", u);
-
printf("\n");
printf("Pre-computed 1/(pi/1024):\n");
mpfr_const_pi(pi, MPFR_RNDN);
--- a/lib/math/sin-impl.myr
+++ b/lib/math/sin-impl.myr
@@ -53,9 +53,9 @@
/* Pi/2 in lots of detail, for range reducing sin(2^18) or so */
const pi_over_2 : uint64[4] = [
0x3ff921fb54442d18,
- 0x3c81a62633145c07,
- 0xb8ff1976b7ed8fbc,
- 0x3584cf98e804177d,
+ 0x3c91a62633145c07,
+ 0xb91f1976b7ed8fbc,
+ 0x35b4cf98e804177d,
]
/* Pre-computed inverses */