reduce: Reduce a group of HDF5 datasets by accumulation (generic)

In BigDataStatMeth: Title: Scalable Statistical Computing with HDF5-Backed Matrices

Reduce a group of HDF5 datasets by accumulation (generic)

Description

Generic function for reducing (accumulating) all datasets in the same HDF5 group as x into a single dataset using a binary operation.

Usage

reduce(x, ...)

Arguments

x	An HDF5Matrix.
...	Additional arguments forwarded to the method.

Value

A new HDF5Matrix containing the accumulated result.

See Also

hdf5_reduce for the standalone group-level version.

Examples

fn <- tempfile(fileext = ".h5")

# Create three matrices in the same group
hdf5_create_matrix(fn, "partials/chunk_0", data = matrix(1:100, 10, 10))
hdf5_create_matrix(fn, "partials/chunk_1", data = matrix(1:100, 10, 10))
hdf5_create_matrix(fn, "partials/chunk_2", data = matrix(1:100, 10, 10))

# Open one as entry point — reduce() operates on its whole group
partial <- hdf5_matrix(fn, "partials/chunk_0")
total   <- reduce(partial, func = "+")
dim(total)

hdf5_close_all()
unlink(fn)

BigDataStatMeth documentation built on May 15, 2026, 1:07 a.m.