text: atan(n) {
      if (typeof n != 'object' || BigNumber.isBigNumber(n)) {
  		n = BigNumber.isBigNumber(n) == true ? n.toNumber() : n
          n = [n]
      }
  	let result = []
      for (var i = 0; i < n.length; i++) {
      	result.push(Math.atan(n[i]).toFixed(15))
      }
  	return result.length == 1 ? result[0] : result
  }
  