1 files changed, 154 insertions, 0 deletions
diff --git a/hw6/src/interval.cpp b/hw6/src/interval.cpp
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+/******************************************************************/
+/* This file is part of the homework assignments for CSCI-427/527 */
+/* at The College of William & Mary and authored by Pieter Peers. */
+/* No part of this file, whether altered or in original form, can */
+/* be distributed or used outside the context of CSCI-427/527     */
+/* without consent of either the College of William & Mary or     */
+/* Pieter Peers.                                                  */
+/******************************************************************/
+#include "interval.h"
+#include "constants.h"
+
+//////////////////
+// Constrructor //
+//////////////////
+interval::interval(float lower, float upper)
+{
+  _lower = lower;
+  _upper = upper;
+
+  // ensure that _lower < _upper
+  if(_upper < _lower) std::swap(_upper, _lower);
+}
+
+
+interval::interval(const interval& i)
+{
+  _lower = i._lower;
+  _upper = i._upper;
+}
+
+
+
+///////////////
+// Operators //
+///////////////
+interval& interval::operator=(const interval& i)
+{
+  _assign(i);
+  return *this;
+}
+
+
+interval interval::operator+(float v) const
+{
+  return interval(_lower + v, _upper + v); 
+}
+
+
+interval interval::operator-(float v) const
+{
+  return interval(_lower - v, _upper - v); 
+}
+
+
+interval interval::operator*(float v) const
+{
+  return interval(_lower * v, _upper * v); 
+}
+
+
+interval interval::operator/(float v) const
+{
+  return interval(_lower / v, _upper / v); 
+}
+    
+
+interval& interval::operator+=(float v)
+{
+  _lower += v;
+  _upper += v;
+  return *this;
+}
+
+interval& interval::operator-=(float v)
+{
+  _lower -= v;
+  _upper -= v;
+  return *this;
+}
+
+
+interval& interval::operator*=(float v)
+{
+  _lower *= v;
+  _upper *= v;
+
+  // ensure that _lower < _upper
+  if(_upper < _lower) std::swap(_upper, _lower);
+
+  // Done.
+  return *this;
+}
+
+interval& interval::operator/=(float v)
+{
+  _lower /= v;
+  _upper /= v;
+
+  // ensure that _lower < _upper
+  if(_upper < _lower) std::swap(_upper, _lower);
+
+  // Done.
+  return *this;
+}
+
+
+////////////////
+// Inspectors //
+////////////////
+float interval::lower(void) const
+{
+  return _lower;
+}
+
+
+float interval::upper(void) const
+{
+  return _upper;
+}
+
+
+bool interval::empty(void) const
+{
+  return (_upper - _lower < EPSILON);
+}
+
+
+
+//////////////
+// Mutators //
+//////////////
+void interval::intersect(const interval& i)
+{
+  _lower = std::max(_lower, i._lower);
+  _upper = std::min(_upper, i._upper);
+}
+
+
+
+/////////////////////
+// Private Methods //
+/////////////////////
+void interval::_assign(const interval& i)
+{
+  _lower = i._lower;
+  _upper = i._upper;
+}
+
+
+void interval::_swap(interval& i)
+{
+  std::swap(_lower, i._lower);
+  std::swap(_upper, i._upper);
+}