discrete = values => {
  const isNumeric = n =>
    !Number.isNaN(n) && (Number.isFinite(n) || Math.abs(n) === Infinity);

  return !values.every(isNumeric);
}
check if the given array of values is discrete or not

@param {[]} values: array of values, can be numbers or strings
@return {Boolean}: whether the input array is discrete