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rayshader (version 0.37.3)

resize_matrix: Resize Matrix

Description

Resizes a matrix (preserving contents) by specifying the desired output dimensions or a scaling factor.

Usage

resize_matrix(
  heightmap,
  scale = 1,
  width = NULL,
  height = NULL,
  method = "bilinear"
)

Arguments

heightmap

The elevation matrix.

scale

Default `0.5`. The amount to scale down the matrix. Scales using bilinear interpolation.

width

Default `NULL`. Alternative to `scale` argument. The desired output width. If `width` is less than 1, it will be interpreted as a scaling factor-- e.g. 0.5 would halve the resolution for the width.

height

Default `NULL`. Alternative to `scale` argument. The desired output width. If `height` is less than 1, it will be interpreted as a scaling factor-- e.g. 0.5 would halve the resolution for the height.

method

Default `bilinear`. Method of interpolation. Alteratively `cubic`, which is slightly smoother, although current implementation slightly scales the image.

Examples

Run this code
#Reduce the size of the monterey bay dataset by half

if(run_documentation()) {
montbaysmall = resize_matrix(montereybay, scale=0.5)
montbaysmall %>%
 sphere_shade() %>%
 plot_map()
}
if(run_documentation()) {
#Reduce the size of the monterey bay dataset from 540x540 to 100x100
montbaysmall = resize_matrix(montereybay, width = 100, height = 100)
montbaysmall %>%
 sphere_shade() %>%
 plot_map()
}
if(run_documentation()) {
#Increase the size of the volcano dataset 3x
volcanobig = resize_matrix(volcano, scale=3)
volcanobig %>% 
 sphere_shade() %>%
 plot_map()
}
if(run_documentation()) {
#Increase the size of the volcano dataset 2x, using cubic interpolation
volcanobig = resize_matrix(volcano, scale=3, method="cubic")
volcanobig %>% 
 sphere_shade() %>%
 plot_map()
}

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