circular_window: Circular window

In geocmeans: Implementing Methods for Spatial Fuzzy Unsupervised Classification

Circular window

Description

Create a matrix that can be used as a window when working with rasters. It uses a radius to set to 0 the weights of pixels that are farther than this distance. This is helpful to create circular focals.

Usage

circular_window(radius, res)

Arguments

radius	The size in metres of the radius of the circular focal
res	The width in metres of a pixel. It is assumed that pixels are squares.

Details

The original function comes from here: https://scrogster.wordpress.com/2012/10/05/applying-a-circular-moving-window-filter-to-raster-data-in-r/ but we reworked it to make it faster and to ensure that the result is a matrix with odd dimensions.

Value

A binary weight matrix

Examples

# wide of 100 metres for pixels of 2 metres
window <- circular_window(100, 2)
# row standardisation
window_row_std <- window / sum(window)

geocmeans documentation built on Sept. 12, 2023, 9:06 a.m.