df2mat: Convert a 3-column data.frame (dim1, dim2, value) to a 2-D...

In ggbrain: Create Images of Volumetric Brain Data in NIfTI Format Using 'ggplot2' Syntax

Convert a 3-column data.frame (dim1, dim2, value) to a 2-D matrix

Description

Convert a 3-column data.frame (dim1, dim2, value) to a 2-D matrix

Arguments

df	A data.frame representing a melted 2-D matrix, having columns dim1, dim2, and value
replace_na	if not NULL, this numeric value will be used to replace any NAs in df in the resulting matrix. This is useful if downstream code is not built to handle missing values.

Details

There is virtually no input validation of df. You must pass a data.frame that has dim1, dim2, and value as columns. Otherwise, it will not work as expected.

This is a much faster version of the acast function from reshape2 that works only on 2-D matrix conversions.

Value

The matrix form of the keyed data.frame object

ggbrain documentation built on April 4, 2025, 5:03 a.m.