chiro-canto/public/larynx/scripts/create_colormap.js

const colormap = require('colormap');
const colors = colormap({
    colormap: 'hot',
    nshades: 256,
    format: 'float'
});
// const fs = require('fs');
// fs.writeFile('hot-colormap.json', JSON.stringify(colors));                        
console.log(JSON.stringify(colors));