[lmi-commits] [lmi] master cb924a4 1/8: Translate from Brent's ALGOL more directly

[Greg Chicares]

branch: master
commit cb924a43cc5466362e90e0e8a63a5ba05cf36d36
Author: Gregory W. Chicares <gchicares@sbcglobal.net>
Commit: Gregory W. Chicares <gchicares@sbcglobal.net>

    Translate from Brent's ALGOL more directly
    
    His code is already a bit on the abstruse side, so it's better to
    translate this condition
      if 2×p < 3×m×q - abs(tol×q) ∧ p < abs(0.5×s×q)
    directly instead of "optimizing" the translation.
---
 zero.hpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/zero.hpp b/zero.hpp
index 205329d..46e4880 100644
--- a/zero.hpp
+++ b/zero.hpp
@@ -376,7 +376,7 @@ root_type decimal_root
             s = e;
             e = d;
             if
-                (   p < 1.5 * m * q - std::fabs(tol * q)
+                (   2.0 * p < 3.0 * m * q - std::fabs(tol * q)
                 &&  p < std::fabs(0.5 * s * q)
                 )
                 {
@@ -495,7 +495,7 @@ double brent_zero
             s = e;
             e = d;
             if
-                (   p < 1.5 * m * q - std::fabs(tol * q)
+                (   2.0 * p < 3.0 * m * q - std::fabs(tol * q)
                 &&  p < std::fabs(0.5 * s * q)
                 )
                 {