id_300.js

//
// Ratio Analysis of Reflectance Spectra A4  (abbrv. RARSa4)
//
// General formula: (680nm /800nm)/(r680/r800)
//
// URL https://www.indexdatabase.de/db/si-single.php?sensor_id=96&rsindex_id=300
//

// Initialize parameters
let r800 = 0.910;
let r680 = 0.781;

let index = (B04 / B08) / (r680 / r800);
let min = 0.01;
let max = 97.89;

// colorBlend will return a color when the index is between min and max and white when it is less than min.
// To see black when it is more than max, uncomment the last line of colorBlend.
// The min/max values were computed automatically and may be poorly specified, feel free to change them to tweak the displayed range.

let underflow_color = [1, 1, 1];
let low_color = [208/255, 88/255, 126/255];
let high_color = [241/255, 234/255, 200/255];
let overflow_color = [0, 0, 0];

return colorBlend(index, [min, min, max],
[
	underflow_color,
	low_color,
	high_color,
	//overflow_color // uncomment to see overflows
]);