Package 'grumpy'

Title: Read 'NumPy' '.npy' and '.npz' Files
Description: Lightweight way to read 'NumPy' '.npy' and '.npz' files in R. All data types supported by 'NumPy', with all sizes (converted internally to R native size), both C and 'Fortran' order, and any shape, up to an arbitrary number of dimensions, are supported.
Authors: Hugo Gruson [aut, cre, cph] (ORCID: <https://orcid.org/0000-0002-4094-1476>), Mike Smith [aut, cph] (Original author of portions of the C code migrated from the Rarr package), German Network for Bioinformatics Infrastructure - de.NBI [fnd]
Maintainer: Hugo Gruson <[email protected]>
License: MIT + file LICENSE
Version: 0.1.1
Built: 2026-05-19 14:05:29 UTC
Source: https://github.com/cran/grumpy

Help Index

Convert raw bytes to an R array based on the specified data type information

Description

This is a replacement for readBin() that can handle the various data types and endianness specified in the .npy file header.

Usage

convert_bytes_to_array(bytes, what, shape, size, endian)

Arguments

bytes

A raw vector containing the bytes to convert
what

A character specifying the base type to convert to (e.g., "float", "int", "string", etc.)
shape

A numeric vector with desired shape of the output array
size

A numeric value with the number of bytes per element for the specified type
endian

The endianness of the data ("little", "big", or NA for single-byte types)

Value

An R array containing the converted data, with the specified shape and data type.

Examples

x <- matrix(c(3L, 6L, 2L, 1L, 12L, 0L), nrow = 2, ncol = 3)
x

y <- writeBin(c(x), raw()) |>
  convert_bytes_to_array("int", shape = c(2L, 3L), size = 4L, endian = "little")
y
dim(y)
is.array(y)
storage.mode(y)

Parse a NumPy Array-protocol type strings

Description

Parse a NumPy Array-protocol type strings

Usage

parse_npy_datatype(descr)

Arguments

descr

A NumPy dtype description string, or a list of such strings fo structured dtypes

Value

A list containing the parsed data type information, including the base type, the number of bytes, and the endianness

Examples

parse_npy_datatype(">i8")
parse_npy_datatype("|b1")
parse_npy_datatype(list(c("r", "<i8"), c("g", "<i8"), c("b", "<i8")))

Read a .npy file

Description

Read a .npy file

Usage

read_npy(file)

Arguments

file

Path to the .npy file

Value

An array containing the data from the .npy file

Examples

read_npy(
  system.file("extdata", "test.npy", package = "grumpy")
)

Read a .npz file

Description

Read a .npz file

Usage

read_npz(file)

Arguments

file

Path to the .npz file

Value

A list of arrays containing the data from the .npz file

Examples

read_npz(
  system.file("extdata", "test.npz", package = "grumpy")
)