Returns a list of numbers as fractions of the input number. Eg. 23 in 6 parts = [ 4, 4, 4, 4, 4, 3 ] (smooth) or [ 8, 3, 3, 3, 3, 3 ] (tight).

get-int-parts.js

// Modes:
// "Smooth" spreads the number list so they are as close together as possible (+- 1). E.g. 23 in 6 parts = [ 4, 4, 4, 4, 4, 3 ]
// "Tight" has 1 number with a "rest" value, and the remaining numbers identical to each other. E.g. 23 in 6 parts = [ 8, 3, 3, 3, 3, 3 ]
const Mode = {
	Smooth: 1,
	Tight: 2,
};

function getIntParts(number, numParts, mode = Mode.Smooth) {
	const val = number / numParts;
	const valFloor = Math.floor(val);

	let ret = new Array(numParts).fill(valFloor);
	if (val > valFloor) {
		const remain = number - numParts * valFloor;
		if (mode === Mode.Smooth) {
			for (let index = 0; index < remain; index++) {
				ret[index] += 1;
			}
		} else if (mode === Mode.Tight) {
			ret[0] += remain;
		}
	}

	return ret;
}

const testNum = 1003;
const testNumParts = 9;
const parts = getIntParts(testNum, testNumParts);
console.log({ testNum, testNumParts, parts });

const parts2 = getIntParts(testNum, testNumParts, Mode.Tight);
console.log({ testNum, testNumParts, parts2 });