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Fix precision problem in interval<T>::cos

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Soonho Kong 2013-08-14 23:48:01 -07:00
parent eb29a67395
commit f87b4394d3
1 changed files with 2 additions and 2 deletions
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4
src/interval/interval_def.h
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@ -1166,7 +1166,7 @@ template<typename T> void interval<T>::cos () {
m_lower_open = m_upper_open = false; m_lower_open = m_upper_open = false;
m_lower_inf = m_upper_inf = false; m_lower_inf = m_upper_inf = false;
T const pi_twice = numeric_traits<T>::pi_twice(); T const pi_twice = numeric_traits<T>::pi_twice();
fmod(pi_twice); fmod(interval<T>(numeric_traits<T>::pi_twice_lower(), numeric_traits<T>::pi_twice_upper()));
if(m_upper - m_lower >= pi_twice) { if(m_upper - m_lower >= pi_twice) {
// If the input width is bigger than 2pi, // If the input width is bigger than 2pi,
// it covers whole domain and gets [-1.0, 1.0] // it covers whole domain and gets [-1.0, 1.0]
@ -1178,7 +1178,7 @@ template<typename T> void interval<T>::cos () {
if(m_lower >= numeric_traits<T>::pi_upper()) { if(m_lower >= numeric_traits<T>::pi_upper()) {
// If the input is bigger than pi, we handle it recursively by the fact: // If the input is bigger than pi, we handle it recursively by the fact:
// cos(x) = -cos(x - pi) // cos(x) = -cos(x - pi)
*this -= numeric_traits<T>::pi(); *this -= interval<T>(numeric_traits<T>::pi_lower(), numeric_traits<T>::pi_upper());
cos(); cos();
neg(); neg();
lean_assert(check_invariant()); lean_assert(check_invariant());