https://github.com/saurfang/graphcoloring

Graph Coloring Algorithms for tidygraph
https://github.com/saurfang/graphcoloring

graph-algorithms graph-coloring map-coloring tidygraph

Last synced: 2 months ago
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Graph Coloring Algorithms for tidygraph

• Host: GitHub
• URL: https://github.com/saurfang/graphcoloring
• Owner: saurfang
• License: other
• Created: 2018-09-20T08:12:38.000Z (over 6 years ago)
• Default Branch: master
• Last Pushed: 2020-01-18T20:06:02.000Z (over 5 years ago)
• Last Synced: 2025-03-27T07:35:54.633Z (3 months ago)
• Topics: graph-algorithms, graph-coloring, map-coloring, tidygraph
• Language: R
• Homepage: https://saurfang.github.io/graphcoloring/
• Size: 1.83 MB
• Stars: 18
• Watchers: 2
• Forks: 0
• Open Issues: 1
• Metadata Files:
  • Readme: README.Rmd
  • Changelog: NEWS.md
  • License: LICENSE

Awesome Lists containing this project

README

        
---

output: github_document

---

```{r setup, include = FALSE}

knitr::opts_chunk$set(

  collapse = TRUE,

  comment = "#>",

  fig.path = "man/figures/README-",

  out.width = "100%"

)

```

# graphcoloring

[![Travis build status](https://travis-ci.org/saurfang/graphcoloring.svg?branch=master)](https://travis-ci.org/saurfang/graphcoloring)

[![CRAN status](https://www.r-pkg.org/badges/version/graphcoloring)](https://cran.r-project.org/package=graphcoloring)

[![lifecycle](https://img.shields.io/badge/lifecycle-experimental-orange.svg)](https://www.tidyverse.org/lifecycle/#experimental)

[![Coverage status](https://codecov.io/gh/saurfang/graphcoloring/branch/master/graph/badge.svg)](https://codecov.io/github/saurfang/graphcoloring?branch=master)

`graphcoloring` is a collection of graph coloring algorithms for coloring vertices of a graph such that no two adjacent vertices share the same color. The algorithms

are included via the embedded 'GraphColoring' C++ library, .

## Installation

You can install the released version of graphcoloring from [CRAN](https://CRAN.R-project.org) with:

``` r

install.packages("graphcoloring")

```

Development version can be installed with

```r

devtools::install_github("saurfang/graphcoloring")

```

## Example

`color_*` functions operate under `tidygraph` family and can be used to color nodes within `mutate` context similar to `group_*` functions in `tidygraph`.

```{r example, message=FALSE}

library(graphcoloring)

library(tidygraph)

library(ggraph)

set.seed(42)

play_islands(5, 10, 0.8, 3) %>%

  mutate(color = as.factor(color_dsatur())) %>%

  ggraph(., layout = 'kk') +

  geom_edge_link(aes(alpha = ..index..), show.legend = FALSE) +

  geom_node_point(aes(color = color), size = 7) +

  theme_graph()

```

`graph_coloring_*` functions directly take adjacency lists and returns an integer vector of assigned labels.

For example, this can be used with `sf::st_intersects()` to color a feature collection for visualization.

```{r sf-example, message=FALSE}

library(graphcoloring)

library(USAboundaries)

library(sf)

library(ggplot2)

set.seed(48)

us_states() %>%  

  filter(!(name %in% c("Alaska", "District of Columbia", "Hawaii", "Puerto Rico"))) %>%

  mutate(

    color = st_intersects(.) %>%

      graph_coloring_dsatur() %>%

      as.factor()

  ) %>%

  ggplot() +

  geom_sf(aes(fill = color)) +

  theme_bw()

```