/// <summary>
/// Determines the complement of an <see cref="Interval<T>"/>.
/// </summary>
/// <typeparam name="T">The value type of the interval.</typeparam>
/// <param name="value">An <see cref="Interval<T>"/> reference.</param>
/// <returns>An <see cref="IntervalCollection<T>"/> that contains elements not in the specified interval.</returns>
/// <seealso href="http://en.wikipedia.org/wiki/Complement_(set_theory)">Complement (set theory)</seealso>
public static IntervalCollection <T> ComplementOf <T>(Interval <T> value)
{
if (Interval.IsNullOrEmpty(value))
{
return(new IntervalCollection <T>
(
new Interval <T>(Bound <T> .LowestBound, Bound <T> .UpmostBound)
));
}
var lowerBound = value.LowerBound;
var upperBound = value.UpperBound;
var result = new List <Interval <T> >(2);
if (object.Equals(lowerBound, Bound <T> .LowestBound) && object.Equals(upperBound, Bound <T> .UpmostBound))
{
}
else if (object.Equals(lowerBound, Bound <T> .LowestBound))
{
result.Add(new Interval <T>
(new Bound <T>(BoundType.Lower, Bound.Reverse(upperBound.Direction), upperBound.Value)
, Bound <T> .UpmostBound));
}
else if (object.Equals(upperBound, Bound <T> .UpmostBound))
{
result.Add(new Interval <T>
(Bound <T> .LowestBound
, new Bound <T>(BoundType.Upper, Bound.Reverse(lowerBound.Direction), lowerBound.Value)));
}
else
{
var iLower = Bound <T> .LowestBound;
var iUpper = new Bound <T>(BoundType.Upper, Bound.Reverse(lowerBound.Direction), lowerBound.Value);
var jLower = new Bound <T>(BoundType.Lower, Bound.Reverse(upperBound.Direction), upperBound.Value);
var jUpper = Bound <T> .UpmostBound;
Interval <T> i;
if (Interval.TryParse(iLower, iUpper, out i))
{
result.Add(i);
}
Interval <T> j;
if (Interval.TryParse(jLower, jUpper, out j))
{
result.Add(j);
}
}
return(new IntervalCollection <T>(result));
}
internal static bool TryParse <T>(BoundDirection lowerDirection
, T lowerValue
, T upperValue
, BoundDirection upperDirection
, out Interval <T> result)
{
Bound <T> lowerBound, upperBound;
if (Bound.TryParse(BoundType.Lower, lowerDirection, lowerValue, out lowerBound) &&
Bound.TryParse(BoundType.Upper, upperDirection, upperValue, out upperBound))
{
return(Interval.TryParse(lowerBound, upperBound, out result));
}
result = default(Interval <T>);
return(false);
}