1berry/ruby
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

* ext/bigdecimal/bigdecimal.c (BigDecimal_sqrt): Fix the precision of

Browse Source 
the result BigDecimal of sqrt.
  [Bug #5266] [ruby-dev:44450]

* test/bigdecimal/test_bigdecimal.rb: add tests for the above changes.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@43764 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
This commit is contained in:
mrkn 2013-11-21 12:37:46 +00:00
parent d1d737ae57
commit ff3e585014
3 changed files with 27 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
ChangeLog
View File

@ -1,3 +1,11 @@
Thu Nov 21 21:36:00 2013 Kenta Murata <mrkn@mrkn.jp>
* ext/bigdecimal/bigdecimal.c (BigDecimal_sqrt): Fix the precision of
the result BigDecimal of sqrt.
[Bug #5266] [ruby-dev:44450]
* test/bigdecimal/test_bigdecimal.rb: add tests for the above changes.
Thu Nov 21 18:49:02 2013 Nobuyoshi Nakada <nobu@ruby-lang.org> Thu Nov 21 18:49:02 2013 Nobuyoshi Nakada <nobu@ruby-lang.org>
* gc.c (vm_xrealloc, vm_xfree): use malloc_usable_size() to obtain old * gc.c (vm_xrealloc, vm_xfree): use malloc_usable_size() to obtain old

10
ext/bigdecimal/bigdecimal.c
View File

@ -1591,10 +1591,10 @@ BigDecimal_sqrt(VALUE self, VALUE nFig)
size_t mx, n; size_t mx, n;
GUARD_OBJ(a, GetVpValue(self, 1)); GUARD_OBJ(a, GetVpValue(self, 1));
mx = a->Prec *(VpBaseFig() + 1); mx = a->Prec * (VpBaseFig() + 1);
n = GetPositiveInt(nFig) + VpDblFig() + 1; n = GetPositiveInt(nFig) + VpDblFig() + BASE_FIG;
if(mx <= n) mx = n; if (mx <= n) mx = n;
GUARD_OBJ(c, VpCreateRbObject(mx, "0")); GUARD_OBJ(c, VpCreateRbObject(mx, "0"));
VpSqrt(c, a); VpSqrt(c, a);
return ToValue(c); return ToValue(c);
@ -5654,6 +5654,7 @@ VpSqrt(Real *y, Real *x)
n = (SIGNED_VALUE)y->MaxPrec; n = (SIGNED_VALUE)y->MaxPrec;
if (x->MaxPrec > (size_t)n) n = (ssize_t)x->MaxPrec; if (x->MaxPrec > (size_t)n) n = (ssize_t)x->MaxPrec;
/* allocate temporally variables */ /* allocate temporally variables */
f = VpAlloc(y->MaxPrec * (BASE_FIG + 2), "#1"); f = VpAlloc(y->MaxPrec * (BASE_FIG + 2), "#1");
r = VpAlloc((n + n) * (BASE_FIG + 2), "#1"); r = VpAlloc((n + n) * (BASE_FIG + 2), "#1");
@ -5691,8 +5692,7 @@ VpSqrt(Real *y, Real *x)
if (VpIsZero(f)) goto converge; if (VpIsZero(f)) goto converge;
VpAddSub(r, f, y, 1); /* r = y + f */ VpAddSub(r, f, y, 1); /* r = y + f */
VpAsgn(y, r, 1); /* y = r */ VpAsgn(y, r, 1); /* y = r */
if (f->exponent <= prec) goto converge; } while (++nr < n);
} while(++nr < n);
#ifdef BIGDECIMAL_DEBUG #ifdef BIGDECIMAL_DEBUG
if (gfDebug) { if (gfDebug) {

14
test/bigdecimal/test_bigdecimal.rb
View File

@ -804,6 +804,20 @@ class TestBigDecimal < Test::Unit::TestCase
assert_equal(1, BigDecimal.new("1").sqrt(1)) assert_equal(1, BigDecimal.new("1").sqrt(1))
end end
def test_sqrt_5266
x = BigDecimal('2' + '0'*100)
assert_equal('0.14142135623730950488016887242096980785696718753769480731',
x.sqrt(56).to_s(56).split(' ')[0])
assert_equal('0.1414213562373095048801688724209698078569671875376948073',
x.sqrt(55).to_s(55).split(' ')[0])
x = BigDecimal('2' + '0'*200)
assert_equal('0.14142135623730950488016887242096980785696718753769480731766797379907324784621070388503875343276415727350138462',
x.sqrt(110).to_s(110).split(' ')[0])
assert_equal('0.1414213562373095048801688724209698078569671875376948073176679737990732478462107038850387534327641572735013846',
x.sqrt(109).to_s(109).split(' ')[0])
end
def test_fix def test_fix
x = BigDecimal.new("1.1") x = BigDecimal.new("1.1")
assert_equal(1, x.fix) assert_equal(1, x.fix)