matrix_to_nr: Convert a numeric matrix to native raster image

In nara: Native Raster Image Tools

Convert a numeric matrix to native raster image

Description

Convert a numeric matrix to native raster image

Usage

matrix_to_nr(mat, palette, fill = "transparent", min = 0, max = 1, dst = NULL)

Arguments

mat	integer matrix
palette	vector of colors. For an integer matrix, this palette must contain at least as many colors as the maximum integer value in mat. For a numeric matrix, any length palette is allowed, and the nearest corresponding color is chosen (no interpolation is done).
fill	Color to be used for values < 1 when input is an integer matrix. Default: 'transparent'.
min, max	assumed range for the numeric data. values from the palette will be interpolated using this range as the extents. An error will occur if a value lies outside this range. Default: (0, 1)
dst	destination native raster image. If NULL (the default) a new native raster image will be created If a native raster image is supplied here, it must have the exact dimensions to match the matrix

Value

native raster image

See Also

Other conversion functions: magick_to_nr(), nr_to_raster(), nrs_to_gif(), nrs_to_mp4()

Examples

# integer matrix
m <- matrix(1:12, 3, 4)
m
palette <- rainbow(12)
nr <- matrix_to_nr(m, palette) 
plot(nr)


# numeric matrix
m <- matrix(runif(20 * 30), 20, 30)
palette <- c('red', 'blue', 'black', 'green', 'blue', 'yellow')
nr <- matrix_to_nr(m, palette)
plot(nr)

nara documentation built on May 28, 2026, 5:07 p.m.