* math.c (math_log1, math_log2, math_log10): refactoring

and tests for this.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@49979 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
This commit is contained in:
gogotanaka 2015-03-16 08:39:29 +00:00
Родитель c7988fd29d
Коммит dc37d6daba
2 изменённых файлов: 21 добавлений и 23 удалений

41
math.c
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@ -495,7 +495,7 @@ math_log(int argc, const VALUE *argv, VALUE obj)
static double
math_log1(VALUE x)
{
double d0, d;
double d;
size_t numbits;
if (RB_BIGNUM_TYPE_P(x) && BIGNUM_POSITIVE_P(x) &&
@ -507,15 +507,13 @@ math_log1(VALUE x)
numbits = 0;
}
d0 = Get_Double(x);
d = Get_Double(x);
/* check for domain error */
if (d0 < 0.0) domain_error("log");
if (d < 0.0) domain_error("log");
/* check for pole error */
if (d0 == 0.0) return -INFINITY;
d = log(d0);
if (numbits)
d += numbits * log(2); /* log(2**numbits) */
return d;
if (d == 0.0) return -INFINITY;
return log(d) + numbits * log(2); /* log(d * 2 ** numbits) */
}
#ifndef log2
@ -550,7 +548,7 @@ extern double log2(double);
static VALUE
math_log2(VALUE obj, VALUE x)
{
double d0, d;
double d;
size_t numbits;
if (RB_BIGNUM_TYPE_P(x) && BIGNUM_POSITIVE_P(x) &&
@ -562,14 +560,13 @@ math_log2(VALUE obj, VALUE x)
numbits = 0;
}
d0 = Get_Double(x);
d = Get_Double(x);
/* check for domain error */
if (d0 < 0.0) domain_error("log2");
if (d < 0.0) domain_error("log2");
/* check for pole error */
if (d0 == 0.0) return DBL2NUM(-INFINITY);
d = log2(d0);
d += numbits;
return DBL2NUM(d);
if (d == 0.0) return DBL2NUM(-INFINITY);
return DBL2NUM(log2(d) + numbits); /* log2(d * 2 ** numbits) */
}
/*
@ -591,7 +588,7 @@ math_log2(VALUE obj, VALUE x)
static VALUE
math_log10(VALUE obj, VALUE x)
{
double d0, d;
double d;
size_t numbits;
if (RB_BIGNUM_TYPE_P(x) && BIGNUM_POSITIVE_P(x) &&
@ -603,15 +600,13 @@ math_log10(VALUE obj, VALUE x)
numbits = 0;
}
d0 = Get_Double(x);
d = Get_Double(x);
/* check for domain error */
if (d0 < 0.0) domain_error("log10");
if (d < 0.0) domain_error("log10");
/* check for pole error */
if (d0 == 0.0) return DBL2NUM(-INFINITY);
d = log10(d0);
if (numbits)
d += numbits * log10(2); /* log10(2**numbits) */
return DBL2NUM(d);
if (d == 0.0) return DBL2NUM(-INFINITY);
return DBL2NUM(log10(d) + numbits * log10(2)); /* log10(d * 2 ** numbits) */
}
/*

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@ -150,6 +150,7 @@ class TestMath < Test::Unit::TestCase
check(1, Math.log(10, 10))
check(2, Math.log(100, 10))
check(Math.log(2.0 ** 64), Math.log(1 << 64))
check(Math.log(2) * 1024.0, Math.log(2 ** 1024))
assert_nothing_raised { assert_infinity(Math.log(1.0/0)) }
assert_nothing_raised { assert_infinity(-Math.log(+0.0)) }
assert_nothing_raised { assert_infinity(-Math.log(-0.0)) }
@ -164,6 +165,7 @@ class TestMath < Test::Unit::TestCase
check(1, Math.log2(2))
check(2, Math.log2(4))
check(Math.log2(2.0 ** 64), Math.log2(1 << 64))
check(1024.0, Math.log2(2 ** 1024))
assert_nothing_raised { assert_infinity(Math.log2(1.0/0)) }
assert_nothing_raised { assert_infinity(-Math.log2(+0.0)) }
assert_nothing_raised { assert_infinity(-Math.log2(-0.0)) }
@ -175,6 +177,7 @@ class TestMath < Test::Unit::TestCase
check(1, Math.log10(10))
check(2, Math.log10(100))
check(Math.log10(2.0 ** 64), Math.log10(1 << 64))
check(Math.log10(2) * 1024, Math.log10(2 ** 1024))
assert_nothing_raised { assert_infinity(Math.log10(1.0/0)) }
assert_nothing_raised { assert_infinity(-Math.log10(+0.0)) }
assert_nothing_raised { assert_infinity(-Math.log10(-0.0)) }