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authorSiddhesh Poyarekar <siddhesh@redhat.com>2012-12-29 06:56:04 +0530
committerSiddhesh Poyarekar <siddhesh@redhat.com>2012-12-29 06:56:04 +0530
commit085ec079e37b0013b421c97b467c6b8ea36a1289 (patch)
tree9a1c10530befa9e1e2358a425d9857d693ae7463 /sysdeps/ieee754/dbl-64/e_pow.c
parentc93c5dec54a64563ce85b511053bd22161085d77 (diff)
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Demystify the magic number 134217729.0
The number 134217729.0 gets used in various places in e_pow.c but
there is no explanation of what that number is.  Add that explanation.
Diffstat (limited to 'sysdeps/ieee754/dbl-64/e_pow.c')
-rw-r--r--sysdeps/ieee754/dbl-64/e_pow.c8
1 files changed, 4 insertions, 4 deletions
diff --git a/sysdeps/ieee754/dbl-64/e_pow.c b/sysdeps/ieee754/dbl-64/e_pow.c
index 513171891c..1d535cb6e3 100644
--- a/sysdeps/ieee754/dbl-64/e_pow.c
+++ b/sysdeps/ieee754/dbl-64/e_pow.c
@@ -95,10 +95,10 @@ __ieee754_pow(double x, double y) {
     if (ABS (y) < 0x1p-64)
       y = y < 0 ? -0x1p-64 : 0x1p-64;
     z = log1(x,&aa,&error);                                 /* x^y  =e^(y log (X)) */
-    t = y*134217729.0;
+    t = y*CN;
     y1 = t - (t-y);
     y2 = y - y1;
-    t = z*134217729.0;
+    t = z*CN;
     a1 = t - (t-z);
     a2 = (z - a1)+aa;
     a = y1*a1;
@@ -182,10 +182,10 @@ SECTION
 power1(double x, double y) {
   double z,a,aa,error, t,a1,a2,y1,y2;
   z = my_log2(x,&aa,&error);
-  t = y*134217729.0;
+  t = y*CN;
   y1 = t - (t-y);
   y2 = y - y1;
-  t = z*134217729.0;
+  t = z*CN;
   a1 = t - (t-z);
   a2 = z - a1;
   a = y*z;