javascript - 使用 Javascript UDF 计算 IRR 时出错

Question

我正在使用标准 SQL 和 javascript UDF 在 bigquery 中编写查询，我遇到了错误“错误:语法错误:预期为“<”但得到了“)”；无法解析 [1 处的 CREATE [TEMP] FUNCTION 语句:47]”。下面是命令行。请有人帮忙。非常感谢。

CREATE TEMPORARY FUNCTION IRRCalc(CArray ARRAY)
RETURNS FLOAT64
LANGUAGE js AS """
function IRRCalc(CArray){
  min = 0.0;
  max = 1.0;
  do {
    guess = (min + max) / 2;
    NPV = 0.0;
    for (var j=0; j<CArray.length; j++){
      NPV += CArray[j]/Math.pow((1+guess),j);
    }
    if (NPV > 0){
      min = guess;
    }
    else {
      max = guess;
    }
  } while (Math.abs(NPV) > 0.00000001);
  return guess * 100;
}

""";

WITH Input AS
  (SELECT [-100, 100, 100, 100, 100, 100] as CArray
   UNION ALL
   SELECT [-100, 100, 100, 100, 100] as CArray)

SELECT 
  CArray,
  IRRCalc(CArray) as IRR
FROM Input as t;

Answer 1

如错误声明所述:Expected "<" but got ")"

我认为你只是缺少声明中的类型

CREATE TEMPORARY FUNCTION IRRCalc(CArray ARRAY<INT64>)   

代替

CREATE TEMPORARY FUNCTION IRRCalc(CArray ARRAY)

顺便说一句，看起来你需要清理你的 JS UDF - 见下文

CREATE TEMPORARY FUNCTION IRRCalc(CArray ARRAY<INT64>)
RETURNS FLOAT64
LANGUAGE js AS """
  min = 0.0;
  max = 1.0;
  do {
    guess = (min + max) / 2;
    NPV = 0.0;
    for (var j=0; j<CArray.length; j++){
      NPV += CArray[j]/Math.pow((1+guess),j);
    }
    if (NPV > 0){
      min = guess;
    }
    else {
      max = guess;
    }
  } while (Math.abs(NPV) > 0.00000001);
  return guess * 100;
""";

WITH Input AS
  (SELECT [-100, 100, 100, 100, 100, 100] as CArray
   UNION ALL
   SELECT [-100, 100, 100, 100, 100] as CArray)

SELECT 
  CArray,
  IRRCalc(CArray) as IRR
FROM Input as t