> Zip <TOutItem, TFirstItem>(
BuiltInEnumerable <TFirstItem> first,
RangeEnumerable second,
Func <TFirstItem, int, TOutItem> resultSelector
)
{
var firstBridged = Bridge(first, nameof(first));
if (second.IsDefaultValue())
{
throw CommonImplementation.Uninitialized(nameof(second));
}
if (resultSelector == null)
{
throw CommonImplementation.ArgumentNull(nameof(resultSelector));
}
return
(CommonImplementation.ZipImpl <
TOutItem,
TFirstItem,
int,
BuiltInEnumerable <TFirstItem>,
BuiltInEnumerator <TFirstItem>,
RangeEnumerable,
RangeEnumerator
>(RefLocal(firstBridged), ref second, resultSelector));
}
// RangeEnumerable
public double Average(RangeEnumerable source)
{
if (source.IsDefaultValue())
{
throw CommonImplementation.Uninitialized(nameof(source));
}
if (source.InnerCount == 0)
{
throw CommonImplementation.SequenceEmpty();
}
// 4 5 6
// ^
// 1 2 3 4
// ^
var leftIx = source.InnerCount / 2;
double left = source.Start + leftIx;
if (source.InnerCount % 2 == 0)
{
// even
double right = left + 1;
return((left + right) / 2.0);
}
else
{
// odd
return(left);
}
}
// RangeEnumerable
public int Sum(RangeEnumerable source)
{
if (source.IsDefaultValue())
{
throw CommonImplementation.Uninitialized(nameof(source));
}
if (source.InnerCount == 0)
{
return(0);
}
long first = source.Start;
long last = first + source.InnerCount - 1;
var length = source.InnerCount;
// https://math.stackexchange.com/a/50487/111
// sum of range [a, b] = (a + b) / 2 * ((b - a) + 1)
// count = b - a + 1
// 2 * sum = (a + b) * ((b - a) + 1)
// 0 1 2 3
// a = 0
// b = 3
// (a + b) = 3
// (b - a) + 1 = 4
// (a + b) * ((b - a) + 1) = 12
// sum = 12 / 2 = 6
// 1 2 3 4 5
// a = 1
// b = 5
// (a + b) = 6
// (b - a) + 1 = 5
// (a + b) * ((b - a) + 1) = 30
// sum = 30 / 2 = 15
long twiceSum = (first + last);
twiceSum *= length;
long ret = twiceSum / 2;
checked
{
return((int)ret);
}
}
> Except(
BuiltInEnumerable <int> first,
RangeEnumerable second
)
{
var firstBridge = Bridge(first, nameof(first));
if (second.IsDefaultValue())
{
throw CommonImplementation.Uninitialized(nameof(second));
}
return(CommonImplementation.ExceptImpl <
int,
BuiltInEnumerable <int>,
BuiltInEnumerator <int>,
RangeEnumerable,
RangeEnumerator
>(RefLocal(firstBridge), ref second));
}
> Join <TOutItem, TJoinKeyItem, TJoinLeftItem>(
BuiltInEnumerable <TJoinLeftItem> outer,
RangeEnumerable inner,
Func <TJoinLeftItem, TJoinKeyItem> outerKeySelector,
Func <int, TJoinKeyItem> innerKeySelector,
Func <TJoinLeftItem, int, TOutItem> resultSelector,
IEqualityComparer <TJoinKeyItem> comparer
)
{
var outerBridge = Bridge(outer, nameof(outer));
if (inner.IsDefaultValue())
{
throw CommonImplementation.Uninitialized(nameof(inner));
}
if (outerKeySelector == null)
{
throw CommonImplementation.ArgumentNull(nameof(outerKeySelector));
}
if (innerKeySelector == null)
{
throw CommonImplementation.ArgumentNull(nameof(innerKeySelector));
}
if (resultSelector == null)
{
throw CommonImplementation.ArgumentNull(nameof(resultSelector));
}
return
(CommonImplementation.JoinImpl <
TOutItem,
TJoinKeyItem,
TJoinLeftItem,
BuiltInEnumerable <TJoinLeftItem>,
BuiltInEnumerator <TJoinLeftItem>,
int,
RangeEnumerable,
RangeEnumerator
>(RefLocal(outerBridge), ref inner, outerKeySelector, innerKeySelector, resultSelector, comparer));
}
> Intersect(
BuiltInEnumerable <int> first,
RangeEnumerable second,
IEqualityComparer <int> comparer
)
{
var firstBridge = Bridge(first, nameof(first));
if (second.IsDefaultValue())
{
throw CommonImplementation.Uninitialized(nameof(second));
}
return(CommonImplementation.IntersectImpl <
int,
BuiltInEnumerable <int>,
BuiltInEnumerator <int>,
RangeEnumerable,
RangeEnumerator
>(RefLocal(firstBridge), ref second, comparer));
}
> GroupJoin <TResult, TGroupJoinKey, TOuter>(
BuiltInEnumerable <TOuter> outer,
RangeEnumerable inner,
Func <TOuter, TGroupJoinKey> outerKeySelector,
Func <int, TGroupJoinKey> innerKeySelector,
Func <TOuter, GroupedEnumerable <TGroupJoinKey, int>, TResult> resultSelector,
IEqualityComparer <TGroupJoinKey> comparer
)
{
var outerBridge = Bridge(outer, nameof(outer));
if (inner.IsDefaultValue())
{
throw CommonImplementation.Uninitialized(nameof(inner));
}
if (outerKeySelector == null)
{
throw CommonImplementation.ArgumentNull(nameof(outerKeySelector));
}
if (innerKeySelector == null)
{
throw CommonImplementation.ArgumentNull(nameof(innerKeySelector));
}
if (resultSelector == null)
{
throw CommonImplementation.ArgumentNull(nameof(resultSelector));
}
return
(CommonImplementation.GroupJoinImpl <
TResult,
TGroupJoinKey,
TOuter,
BuiltInEnumerable <TOuter>,
BuiltInEnumerator <TOuter>,
int,
RangeEnumerable,
RangeEnumerator
>(RefLocal(outerBridge), ref inner, outerKeySelector, innerKeySelector, resultSelector, comparer));
}