als-statistics/lib/ratio-column/instruments/mode.js

A powerful and lightweight JavaScript library for descriptive statistics, regression, clustering, outlier detection, and noise analysis using a flexible table/column architecture.

function mode(values) {
   const freq = new Map();
   let maxFreq = 0;
   for (let num of values) {
      const count = (freq.get(num) || 0) + 1;
      freq.set(num, count);
      if (count > maxFreq) maxFreq = count;
   }

   const modes = [];
   for (const [val, count] of freq.entries()) {
      if (count === maxFreq) modes.push(val);
   }
   return modes.length === values.length ? [] : modes;
}

module.exports = mode