public static void Aggregate_Sum(Labeled <ParallelQuery <int> > labeled, int count)
{
ParallelQuery <int> query = labeled.Item;
if (count == 0)
{
Assert.Throws <InvalidOperationException>(() => query.Aggregate((x, y) => x + y));
}
else
{
// The operation will overflow for long-running sizes, but that's okay:
// The helper is overflowing too!
Assert.Equal(Functions.SumRange(0, count), query.Aggregate((x, y) => x + y));
}
}
/// <summary>Takes the top elements as if they were sorted.</summary>
/// <typeparam name="TSource">Specifies the type of the elements.</typeparam>
/// <typeparam name="TKey">Specifies the type of the keys used to compare elements.</typeparam>
/// <param name="source">The source elements.</param>
/// <param name="keySelector">A function used to extract a key from each element.</param>
/// <param name="count">The number of elements to take.</param>
/// <returns></returns>
public static IEnumerable <TSource> TakeTop <TSource, TKey>(this ParallelQuery <TSource> source,
Func <TSource, TKey> keySelector,
int count)
{
// We want to sort in descending order, so we need the opposite of the default comparer
var comparer = new DescendingDefaultComparer <TKey>();
// Aggregate, using a sorted list per thread to keep track of the best N elements,
// then merge those at the end.
return(source.Aggregate(
() => new Nequeo.Linq.Common.SortedTopN <TKey, TSource>(count, comparer),
(accum, item) =>
{
accum.Add(keySelector(item), item);
return accum;
},
(accum1, accum2) =>
{
foreach (var item in accum2)
{
accum1.Add(item);
}
return accum1;
},
(accum) => accum.Values));
}
/// <summary>
/// 정렬이 되었다면, 지정된 갯수의 최상위 요소중 <paramref name="count"/> 수만큼 반환합니다.
/// </summary>
/// <typeparam name="TSource">요소의 수형</typeparam>
/// <typeparam name="TKey">요소 비교를 위한 Key의 수형</typeparam>
/// <param name="source">요소 집합</param>
/// <param name="keySelector">요소로부터 Key를 추출하는 Selector</param>
/// <param name="count">취할 요소의 수</param>
/// <returns></returns>
public static IEnumerable <TSource> TakeTop <TSource, TKey>(this ParallelQuery <TSource> source,
Func <TSource, TKey> keySelector,
int count = 1)
{
keySelector.ShouldNotBeNull("keySelector");
if (IsDebugEnabled)
{
log.Debug("최상의 요소 중 [{0}]만큼 열거합니다.", count);
}
var comparer = new DescendingDefaultComparer <TKey>();
return
(source.Aggregate(() => new SortedTopN <TKey, TSource>(count, comparer),
(accum, item) => {
accum.Add(keySelector(item), item);
return accum;
},
(accum1, accum2) => {
foreach (var item in accum2)
{
accum1.Add(item);
}
return accum1;
},
accum => accum.Values));
}
/// <summary>
/// An aggregate parallel query to return the minimum and the maximum of <paramref name="data"/> together, faster than two successive parallel queries to minimum and maximum.
/// </summary>
/// <param name="data">The list whose extrema we are to find.</param>
/// <returns>A <see cref="Tuple{double, double}"/> instance whose <see cref="Tuple{double, double}.Item1"/> represents the minimum and whose <see cref="Tuple{double, double}.Item2"/> contains the maximum of <paramref name="data"/>.</returns>
public static Tuple <double, double> Extrema(this IList <double> data)
{
ParallelQuery <double> query = data.AsParallel();
return(query.Aggregate(
// Initialise accumulator:
() => new ExtremumAccumulator()
{
Min = Double.MaxValue, Max = Double.MinValue
},
// Aggregate calculations:
(accumulator, item) => { if (item < accumulator.Min)
{
accumulator.Min = item;
}
if (item > accumulator.Max)
{
accumulator.Max = item;
}
return accumulator; },
// Combine accumulators:
(accumulator1, accumulator2) => new ExtremumAccumulator()
{
Min = Math.Min(accumulator1.Min, accumulator2.Min), Max = Math.Max(accumulator1.Max, accumulator2.Max)
},
// Get result:
accumulator => new Tuple <double, double>(accumulator.Min, accumulator.Max)
));
}
public static void Aggregate_Product_Seed(Labeled <ParallelQuery <int> > labeled, int count, int start)
{
ParallelQuery <int> query = labeled.Item;
// The operation will overflow for long-running sizes, but that's okay:
// The helper is overflowing too!
Assert.Equal(Functions.ProductRange(start, count), query.Aggregate(1L, (x, y) => x * y));
}
public static void Aggregate_Product_SeedFunction(Labeled <ParallelQuery <int> > labeled, int count, int start)
{
ParallelQuery <int> query = labeled.Item;
long actual = query.Aggregate(
() => 1L,
(accumulator, x) => accumulator * x,
(left, right) => left * right,
result => result + ResultFuncModifier);
Assert.Equal(Functions.ProductRange(start, count) + ResultFuncModifier, actual);
}
public static void Aggregate_Collection_SeedFunction(Labeled <ParallelQuery <int> > labeled, int count)
{
ParallelQuery <int> query = labeled.Item;
IList <int> actual = query.Aggregate(
() => (IList <int>) new List <int>(),
(accumulator, x) => accumulator.AddToCopy(x),
(left, right) => left.ConcatCopy(right),
result => result.OrderBy(x => x).ToList());
Assert.Equal(Enumerable.Range(0, count), actual);
}
public static void Aggregate_Collection_SeedFunction(int count)
{
ParallelQuery <int> query = UnorderedSources.Default(count);
IList <int> actual = query.Aggregate(
() => ImmutableList <int> .Empty,
(accumulator, x) => accumulator.Add(x),
(left, right) => left.AddRange(right),
result => result.OrderBy(x => x).ToList());
Assert.Equal(Enumerable.Range(0, count), actual);
}
public static void Aggregate_Sum_SeedFunction(Labeled <ParallelQuery <int> > labeled, int count)
{
ParallelQuery <int> query = labeled.Item;
int actual = query.Aggregate(
() => 0,
(accumulator, x) => accumulator + x,
(left, right) => left + right,
result => result + ResultFuncModifier);
Assert.Equal(Functions.SumRange(0, count) + ResultFuncModifier, actual);
}
public static void Aggregate_Product_SeedFunction(int count)
{
ParallelQuery <int> query = ParallelEnumerable.Range(1, count);
long actual = query.Aggregate(
() => 1L,
(accumulator, x) => unchecked (accumulator * x),
(left, right) => left * right,
result => result + ResultFuncModifier);
Assert.Equal(Functions.ProductRange(1, count) + ResultFuncModifier, actual);
}
public static void Aggregate_Sum_SeedFunction(int count)
{
ParallelQuery <int> query = UnorderedSources.Default(count);
int actual = query.Aggregate(
() => 0,
(accumulator, x) => accumulator + x,
(left, right) => left + right,
result => result + ResultFuncModifier);
Assert.Equal(Functions.SumRange(0, count) + ResultFuncModifier, actual);
}
public void AggregateTestCase()
{
ParallelTestHelper.Repeat(() => {
ParallelQuery <int> range = ParallelEnumerable.Repeat(5, 2643);
double average = range.Aggregate(() => new double[2],
(acc, elem) => { acc[0] += elem; acc[1]++; return(acc); },
(acc1, acc2) => { acc1[0] += acc2[0]; acc1[1] += acc2[1]; return(acc1); },
acc => acc[0] / acc[1]);
Assert.AreEqual(5.0, average, "#1");
});
}
public static void InvokeJH()
{
List <int> numList = new List <int> {
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
};
ParallelQuery <int> pList = numList.AsParallel();
var pResult = pList.Aggregate(
(result, item) =>
{
result += item;
return(result);
}
);
Console.WriteLine(pResult);
var parallelQuery = from t in GetTypes().AsParallel() select t;
//第一个参数种子值为累加器的初始值
var parallelAggregator = parallelQuery.Aggregate(
() =>
{
ConcurrentDictionary <char, int> cdic = new ConcurrentDictionary <char, int>();
cdic.TryAdd('#', 9595);
return(cdic);
},
//对单个分区的处理 返回单个分区结果
(taskTotal, item) => AccumulateLettersInfomation(taskTotal, item),
//对单个分区结果进行聚合，返回最终累加器结果
(total, taskTotal) => MergeAccumulators(taskTotal),
//对最后结果的的转换
total =>
{
total.TryAdd('-', 10000);
return(total);
});
Console.WriteLine();
Console.WriteLine("There were the names");
var orderedKeys = from k in parallelAggregator.Keys
orderby parallelAggregator[k] descending
select k;
foreach (var c in orderedKeys)
{
Console.WriteLine("letter {0} --- {1}times", c, parallelAggregator[c]);
}
}
/// <summary>Takes the top elements as if they were sorted.</summary>
/// <typeparam name="TSource">Specifies the type of the elements.</typeparam>
/// <typeparam name="TKey">Specifies the type of the keys used to compare elements.</typeparam>
/// <param name="source">The source elements.</param>
/// <param name="keySelector">A function used to extract a key from each element.</param>
/// <param name="count">The number of elements to take.</param>
/// <returns></returns>
public static IEnumerable <TSource> TakeTop <TSource, TKey>(this ParallelQuery <TSource> source,
Func <TSource, TKey> keySelector, int count)
{
ParallelLinqExtensions.DescendingDefaultComparer <TKey> comparer =
new ParallelLinqExtensions.DescendingDefaultComparer <TKey>();
return(source.Aggregate <TSource, SortedTopN <TKey, TSource>, IEnumerable <TSource> >(
(Func <SortedTopN <TKey, TSource> >)(() =>
new SortedTopN <TKey, TSource>(count, (IComparer <TKey>)comparer)),
(Func <SortedTopN <TKey, TSource>, TSource, SortedTopN <TKey, TSource> >)((accum, item) =>
{
accum.Add(keySelector(item), item);
return accum;
}), (Func <SortedTopN <TKey, TSource>, SortedTopN <TKey, TSource>, SortedTopN <TKey, TSource> >)((accum1,
accum2) =>
{
foreach (KeyValuePair <TKey, TSource> keyValuePair in accum2)
{
accum1.Add(keyValuePair);
}
return accum1;
}), (Func <SortedTopN <TKey, TSource>, IEnumerable <TSource> >)(accum => accum.Values)));
}
/// <summary>Takes the top elements as if they were sorted.</summary>
/// <typeparam name="TSource">Specifies the type of the elements.</typeparam>
/// <typeparam name="TKey">Specifies the type of the keys used to compare elements.</typeparam>
/// <param name="source">The source elements.</param>
/// <param name="keySelector">A function used to extract a key from each element.</param>
/// <param name="count">The number of elements to take.</param>
/// <returns></returns>
public static IEnumerable <TSource> TakeTop <TSource, TKey>(this ParallelQuery <TSource> source,
Func <TSource, TKey> keySelector, int count)
{
DescendingDefaultComparer <TKey> comparer =
new DescendingDefaultComparer <TKey>();
return(source.Aggregate(
() =>
new SortedTopN <TKey, TSource>(count, comparer),
(accum, item) =>
{
accum.Add(keySelector(item), item);
return accum;
}, (accum1,
accum2) =>
{
foreach (KeyValuePair <TKey, TSource> keyValuePair in accum2)
{
accum1.Add(keyValuePair);
}
return accum1;
}, accum => accum.Values));
}
public static void Aggregate_Sum_Seed(Labeled <ParallelQuery <int> > labeled, int count)
{
ParallelQuery <int> query = labeled.Item;
Assert.Equal(Functions.SumRange(0, count), query.Aggregate(0, (x, y) => x + y));
}
public static void Aggregate_Collection_Results(Labeled <ParallelQuery <int> > labeled, int count)
{
ParallelQuery <int> query = labeled.Item;
Assert.Equal(Enumerable.Range(0, count), query.Aggregate((IList <int>) new List <int>(), (l, x) => l.AddToCopy(x), l => l.OrderBy(x => x)));
}
public static void Aggregate_Product_Result(Labeled <ParallelQuery <int> > labeled, int count, int start)
{
ParallelQuery <int> query = labeled.Item;
Assert.Equal(Functions.ProductRange(start, count) + ResultFuncModifier, query.Aggregate(1L, (x, y) => x * y, result => result + ResultFuncModifier));
}
public static void Aggregate_Sum_Result(Labeled <ParallelQuery <int> > labeled, int count)
{
ParallelQuery <int> query = labeled.Item;
Assert.Equal(Functions.SumRange(0, count) + ResultFuncModifier, query.Aggregate(0, (x, y) => x + y, result => result + ResultFuncModifier));
}