dqddot: High-accuracy dot product

In bigalgebra: 'BLAS' and 'LAPACK' Routines for Native R Matrices and 'big.matrix' Objects

High-accuracy dot product

Description

Forms the dot product using long-double accumulation to mitigate rounding error.

Usage

dqddot(N = NULL, X, INCX = 1L, Y, INCY = 1L)

Arguments

N	Optional integer giving the number of elements. Defaults to 'length(X)'.
X	Double-precision vector, matrix or ['bigmemory::big.matrix'] input.
INCX	Integer stride for traversing 'X'.
Y	Double-precision object updated in place.
INCY	Integer stride for traversing 'Y'.

Value

Numeric scalar equal to the dot product of 'X' and 'Y'.

Examples

dqddot(X = 1:3, Y = c(2, 4, 6))

bigalgebra documentation built on Sept. 9, 2026, 5:12 p.m.