奇怪的错误：方法定义中省略的形式参数不能在签名中

Question

我试图在一个R文件中定义泛型方法，并在另一个R文件中实现它们。 但我得到一个我不明白的错误。

问题：

1. 错误的来源是什么？
2. 如何修复错误？

BuyProbabilityGeneric.R的内容：

setGeneric("FirstTimeBuyProbability",
        valueClass = "numeric",
        function(object, period, price) {
    standardGeneric("FirstTimeBuyProbability")
})

setGeneric("ReturningBuyProbability",
        valueClass = "numeric",
        function(object, period1, price1, period2, price2) {
    standardGeneric("ReturningBuyProbability")
})

BuyProbabilityBasic.R的内容：

setClass("BuyProbabilityBasic", representation(
        full.price.probability = "numeric",
        elasticity = "numeric"))

setMethod("FirstTimeBuyProbability",
        signature(object = "BuyProbabilityBasic", 
                period = "numeric", price = "numeric"), 
        function(object, t, price) {
    full.price.probability * price^elasticity
})

setMethod("ReturningBuyProbability",
        signature(object = "BuyProbabilityBasic", 
                period1 = "numeric", price1 = "numeric",
                period2 = "numeric", price2 = "numeric"), 
        function(object, period1, price1, period2, price2) {
    max(0, FirstTimeBuyProbability(object, period2, price2) -
        FirstTimeBuyProbability(object, period1, price1))
})

R控制台输出：

> source('BuyProbabilityGeneric.R')
> source('BuyProbabilityBasic.R')
Error in conformMethod(signature, mnames, fnames, f, fdef, definition) : 
  in method for ‘FirstTimeBuyProbability’ with signature 
‘object="BuyProbabilityBasic",period="numeric",price="numeric"’: 
formal arguments (period = "numeric") omitted in the method definition
cannot be in the signature

Answer 1

尝试：

setMethod("FirstTimeBuyProbability",
          signature(object = "BuyProbabilityBasic", 
                    period = "numeric", price = "numeric"), 
          function(object, period, price) {
            full.price.probability * price^elasticity
          })

注意我在函数定义形式中如何将t更改为period。基本上，您试图定义一个函数，其中形式与签名冲突。