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Removed unnecessary upfront bernoulli number calculation now that they can be cached

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This commit is contained in:
Nikhar Agrawal
2014-02-07 03:04:55 +05:30
parent 036945c71f
commit 0209dced1d
1 changed files with 2 additions and 36 deletions
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38
include/boost/math/special_functions/detail/polygamma.hpp
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@@ -84,10 +84,6 @@
{
BOOST_MATH_STD_USING
// calculate a high bernoulli number upfront to make use of cache
unsigned int bernoulli_index = 100;
boost::math::bernoulli_b2n<T>(bernoulli_index);
T z(x);
T log_z(log(z));
T one_over_2z= T(1) / (2 * z);
@@ -95,19 +91,7 @@
for(int two_k = 2; two_k < max_iteration<T>::value; two_k += 2)
{
if(two_k/2 > static_cast<boost::int32_t>(bernoulli_index))
{
try
{
int temp = static_cast<int>(bernoulli_index * 1.5F);
boost::math::bernoulli_b2n<T>(temp);
bernoulli_index = temp;
}
catch(...)
{
break;
}
}
T term(1);
T one_over_two_k = T(1) / two_k;
@@ -156,11 +140,7 @@
if(n == 0)
{
return digamma_atinfinityplus(n, x, pol);
}
//TODO try calculating for bernoulli_index= max_iteration, if error then set bernoulli_index=100
unsigned int bernoulli_index = 100;
boost::math::bernoulli_b2n<T>(bernoulli_index);
}
const bool b_negate = ((n % 2) == 0);
@@ -180,20 +160,6 @@
// Perform the Bernoulli series expansion.
for(int two_k = 4; two_k < max_iteration<T>::value; two_k += 2)
{
if((two_k / 2) > static_cast<int>(bernoulli_index))
{
try
{
//TODO the multiplication factor should depend upon T, small precision, smaller multiplication factor
int temp = static_cast<int>(bernoulli_index * 2.0F);
boost::math::bernoulli_b2n<T>(temp);
bernoulli_index = temp;
}
catch(...)
{
break;
}
}
one_over_x_pow_two_k_plus_n *= one_over_z2;
two_k_plus_n_minus_one_fact *= ++two_k_plus_n_minus_one;