当数据量大的时候用普通代码计算非常耗时，这里简单利用simd加速处理

 internal unsafe class Vector256Helper{/// <summary>/// 统计元素个数/// </summary>/// <param name="array"></param>/// <param name="elementToCount">需要统计的元素</param>/// <returns></returns>public static int Count(int[] array, int elementToCount){int count = 0;int vectorSize = Vector256<int>.Count;int limit = array.Length - (array.Length % vectorSize);fixed (int* pArray = array){int* ptr = pArray;var target = Vector256.Create(elementToCount);Vector256<int> equalMask = Vector256<int>.Zero;for (int i = 0; i < limit; i += vectorSize){Vector256<int> vector = *(Vector256<int>*)(ptr + i);equalMask += Avx2.CompareEqual(vector, target);}int* equalMaskPtr = (int*)&equalMask;for (int j = 0; j < vectorSize; j++){count += -*(equalMaskPtr + j);}// 处理剩余的元素for (int i = limit; i < array.Length; i++){if (*(pArray + i) == elementToCount)count++;}}return count;}/// <summary>/// 求和/// </summary>/// <param name="buffer"></param>/// <returns></returns>public static int Sum(int[] buffer){int vectorSize = Vector256<int>.Count;int sum4 = 0;Vector256<int> sumV = Vector256<int>.Zero;int j;int m = buffer.Length - vectorSize;fixed (int* p = buffer){for (j = 0; j <= m; j += vectorSize){sumV += *(Vector256<int>*)(p + j);}int* ptr = (int*)&sumV;for (int i = 0; i < vectorSize; i++){sum4 += *(ptr + i);}// 处理剩余的元素for (; j < buffer.Length; j++){sum4 += *(p + j);}}return sum4;}/// <summary>/// 求平均数/// </summary>/// <param name="buffer"></param>/// <returns></returns>public double Avg(int[] buffer){int sum = Sum(buffer);return sum / (double)buffer.Length;}/// <summary>/// 求最大值/// </summary>/// <param name="array"></param>/// <returns></returns>public static int Max(int[] array){int vectorSize = Vector256<int>.Count;int limit = array.Length - (array.Length % vectorSize);fixed (int* pArray = array){int maxElement = *pArray;Vector256<int> vectorMax = *(Vector256<int>*)(pArray);for (int i = 1; i < limit; i += vectorSize){Vector256<int> vector = *(Vector256<int>*)(pArray + i);vectorMax = Avx2.Max(vectorMax, vector);}int* maxPtr = (int*)&vectorMax;for (int j = 0; j < vectorSize; j++){maxElement = Math.Max(maxElement, *(maxPtr + j));}for (int i = limit; i < array.Length; i++){maxElement = Math.Max(maxElement, *(pArray + i));}return maxElement;}}/// <summary>/// 求最小值/// </summary>/// <param name="array"></param>/// <returns></returns>public static int Min(int[] array){int vectorSize = Vector256<int>.Count;int limit = array.Length - (array.Length % vectorSize);fixed (int* pArray = array){int maxElement = *pArray;Vector256<int> vectorMin = *(Vector256<int>*)(pArray);for (int i = 1; i < limit; i += vectorSize){Vector256<int> vector = *(Vector256<int>*)(pArray + i);vectorMin = Avx2.Min(vectorMin, vector);}int* maxPtr = (int*)&vectorMin;for (int j = 0; j < vectorSize; j++){maxElement = Math.Min(maxElement, *(maxPtr + j));}for (int i = limit; i < array.Length; i++){maxElement = Math.Min(maxElement, *(pArray + i));}return maxElement;}}}