Example #1
0
func (A *Matrix) ScaleBLAS(v float64) {

	// Normal matrices.
	if A.stride == A.width {
		blas.Dscal(len(A.data), v, A.data, 1)
		return
	}

	// Submatrices.
	for i := 0; i < A.height; i++ {
		blas.Dscal(A.width, v, A.Row(i), 1)
	}
}
Example #2
0
File: lv2.go Project: c2-akula/vec
// MVMul multiplies a matrix with a vector
// y = alpha*A*x + y
func MVMul(N, m, n int, alpha float64, A, x, y []float64) {
	if N != n {
		panic("vec: Dimensions invalid. A.Cols() != Vec.Len()")
	}

	if alpha == 0 {
		return
	}

	if alpha == 1 {
		goto alg
	}

	blas.Dscal(N, alpha, A, 1)
	goto alg

alg:
	{
		if N < 8 {
			idx, ptr := 0, 0
			extra := n - n%4
			ub := ((n / 4) * 4) - 1

			for i := 0; i < m; i++ {
				idx = i * n
				for j := 0; j < ub; j += 4 {
					ptr = idx + j
					y[i] += A[ptr]*x[j] + A[ptr+1]*x[j+1] + A[ptr+2]*x[j+2] + A[ptr+3]*x[j+3]
				}
				for j := extra; j < n; j++ {
					y[i] += A[idx+j] * x[j]
				}
			}
			return
		}

		for i := 0; i < m; i++ {
			y[i] += blas.Ddot(N, A[n*i:n*i+n], 1, x, 1)
		}
	}
}
Example #3
0
File: vec.go Project: c2-akula/vec
// Scale multiples vector, x with scalar alpha
func Scale(n int, alpha float64, x []float64) {
	if n == 3 {
		x[0] *= alpha
		x[1] *= alpha
		x[2] *= alpha
	} else if n == 4 {
		x[0] *= alpha
		x[1] *= alpha
		x[2] *= alpha
		x[3] *= alpha
	} else if n == 6 {
		x[0] *= alpha
		x[1] *= alpha
		x[2] *= alpha
		x[3] *= alpha
		x[4] *= alpha
		x[5] *= alpha
	} else {
		blas.Dscal(n, alpha, x, 1)
	}
}
Example #4
0
File: lv2.go Project: c2-akula/vec
func Outer(N, m, n int, alpha float64, A, x, y []float64) {
	if N != n {
		panic("vec: Dimensions invalid. A.Cols() != x.Len()")
	}

	if alpha == 0 {
		return
	}

	if alpha == 1 {
		goto alg
	}

	blas.Dscal(N, alpha, x, 1)
	goto alg

alg:
	{
		for i := 0; i < m; i++ {
			blas.Daxpy(N, x[i], y, 1, A[n*i:n*i+n], 1)
		}
	}
}
Example #5
0
func scal64(alpha float64, X []float64) {
	blas.Dscal(len(X), alpha, X, 1)
}