Matrix Utilities

1 Overview

Diagonal operations and sparse matrix multiplication utilities for HDF5Matrix objects.

2 Functions

2.1 diag_op

Applies an element-wise binary operation between an and a diagonal vector (a 1-row or 1-column ). The vector is broadcast across each row of the matrix.

The standard arithmetic operators (, , , ) dispatch automatically to this function when one operand is a 1-row or 1-column .

2.2 diag_scale

Applies a scalar arithmetic operation to the diagonal elements of an . Off-diagonal elements are not modified. Delegates to .

2.3 diag

Overrides to dispatch on objects. For plain R matrices/vectors the call is forwarded to .

When is an , extracts the diagonal as an in-memory numeric vector (length = min(nrow, ncol)).

2.4 multiply_sparse

Generic function for block-wise sparse matrix multiplication. The method for computes using the BigDataStatMeth sparse multiplication algorithm, which skips all-zero blocks and is more efficient when one or both matrices are highly sparse.

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title: "Matrix Utilities"
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## Overview

Diagonal operations and sparse matrix multiplication utilities for HDF5Matrix objects.

## Functions


### [diag_op](diag_op.qmd)

Applies an element-wise binary operation between an
\code{HDF5Matrix} and a diagonal vector (a 1-row or 1-column
\code{HDF5Matrix}). The vector is broadcast across each row of the
matrix.

The standard arithmetic operators (\code{+}, \code{-}, \code{*},
\code{/}) dispatch automatically to this function when one operand is
a 1-row or 1-column \code{HDF5Matrix}.


### [diag_scale](diag_scale.qmd)

Applies a scalar arithmetic operation to the diagonal elements of an
\code{HDF5Matrix}. Off-diagonal elements are not modified.
Delegates to \code{bdDiag_scalar_hdf5()}.


### [diag](diag.qmd)

Overrides \code{base::diag()} to dispatch on \code{HDF5Matrix} objects.
For plain R matrices/vectors the call is forwarded to \code{base::diag()}.

When \code{x} is an \code{HDF5Matrix}, extracts the diagonal as an
in-memory numeric vector (length = min(nrow, ncol)).


### [multiply_sparse](multiply_sparse.qmd)

Generic function for block-wise sparse matrix multiplication.
The method for \code{HDF5Matrix} computes \code{x \%*\% y} using the
BigDataStatMeth sparse multiplication algorithm, which skips all-zero
blocks and is more efficient when one or both matrices are highly sparse.