static void Main(string[] args) { int num_threads = 2; BLAS.OpenblasSetNumThreads(ref num_threads); float[,] a = new float[, ] { { 1, 2 }, { 3, 4 }, { 5, 6 } }; float[,] b = new float[, ] { { 2, 2, 2 }, { 3, 3, 3 } }; var c = Dot(a, b, 1, 0); Console.ReadLine(); }