/** Compute median of a numeric array. Returns null for empty arrays. */
export function median(values: number[]): number | null {
if (values.length === 0) return null;
const sorted = [...values].sort((a, b) => a - b);
const mid = Math.floor(sorted.length / 2);
if (sorted.length % 2 === 0) {
return (sorted[mid - 1]! + sorted[mid]!) / 2;
}
return sorted[mid]!;
}
/** Compute average of a numeric array. Returns null for empty arrays. */
export function average(values: number[]): number | null {
if (values.length === 0) return null;
return values.reduce((sum, v) => sum + v, 0) / values.length;
}
/** Compute numeric stats (min, max, avg, median) from an array. Returns null for empty arrays. */
export function computeStats(values: number[]): {
min: number;
max: number;
avg: number;
median: number;
} | null {
if (values.length === 0) return null;
const avg = average(values) as number;
const med = median(values) as number;
return {
min: Math.min(...values),
max: Math.max(...values),
avg: Math.round(avg * 100) / 100,
median: Math.round(med * 100) / 100,
};
}
