moving-averages-js/src/common.ts

The FinTech utility collections of simple, cumulative, and exponential moving averages.

export const isNumber = (subject: any): subject is number => {
  return (
    typeof subject === "number" &&
    // is not NaN: `NaN === NaN` => `false`
    subject === subject
  );
};

export const isArray = Array.isArray;