# RgbToCol: Find the Nearest Named R-Color to a Given RGB-Color In DescTools: Tools for Descriptive Statistics

## Description

Converting a RGB-color to a named R-Color means looking for a color in the R-palette, which is nearest to the given RGB-color. This function uses the minimum of squared distance (`"euclidean"`) or the minimum absolute distance (`"manhattan"`) as proximity measure.
`RgbToLong()` converts a RGB-color to a long integer in numeric format. `LongToRGB()` does it the other way round.

## Usage

 ```1 2 3 4``` ```RgbToCol(col, method = "rgb", metric = "euclidean") RgbToLong(col) LongToRgb(col) ```

## Arguments

 `col` the color in rgb code, say a matrix with the red, green and blue code in the rows. `method` character string specifying the color space to be used. Can be `"rgb"` (default) or `"hsv"`. `metric` character string specifying the metric to be used for calculating distances between the colors. Available options are `"euclidean"` (default) and `"manhattan"`. Euclidean distances are root sum-of-squares of differences, and manhattan distances are the sum of absolute differences.

## Details

It may not be clear from the start which method, rgb or hsv, yield the more natural results. Trying and comparing is a recommended strategy. Moreover the shortest numerical distance will not always be the best choice, when comparing the colours visually.

## Value

the name of the nearest found R color.

## Author(s)

Andri Signorell <andri@signorell.net>

`ColToRgb` and the other conversion functions

## Examples

 ```1 2 3``` ```RgbToCol(matrix(c(162,42,42), nrow=3)) RgbToLong(matrix(c(162,42,42), nrow=3)) ```

### Example output

``` "brown"
 2763426
```

DescTools documentation built on June 17, 2021, 5:12 p.m.