Question

我创建了一个函数，用户整齐地询问用户是否要输入3个变量中的每一个，如果是，则每个变量的值应该是多少。我希望函数输出两个向量的列表：输入变量的向量，以及输入值的向量。

gray = (r == b) & (b == g)
print np.all(gray)

然而，我收到错误：

Input <- function() {
    answer <- readline(prompt = "Enter VIEW_ID? y/n ")
    if(answer == "y") { VIEW_ID <- readline(prompt = "Enter value: ") }

    answer <- readline(prompt = "Enter ACTION_TYPE? y/n ")
    if(answer == "y") { ACTION_TYPE <- readline(prompt = "Enter value: ") }

    answer <- readline(prompt = "Enter CLIENT_ID? y/n ")
    if(answer == "y") { CLIENT_ID <- readline(prompt = "Enter value: ") }

    rm(answer)

    VarsValues <- list(ls(), sapply(ls(), get)) 
    VarsValues
}

我不明白为什么这不起作用。当我在全局环境中尝试它时，> Input() Enter VIEW_ID? y/n y Enter value: a Enter ACTION_TYPE? y/n y Enter value: b Enter CLIENT_ID? y/n y Enter value: c Error in FUN(X[[i]], ...) : object 'ACTION_TYPE' not found工作正常，打印每个变量的值。

Answer 1

您需要为get指定环境。这应该有效：

Input <- function() {
  answer <- readline(prompt = "Enter VIEW_ID? y/n ")
  if(answer == "y") { VIEW_ID <- readline(prompt = "Enter value: ") }

  answer <- readline(prompt = "Enter ACTION_TYPE? y/n ")
  if(answer == "y") { ACTION_TYPE <- readline(prompt = "Enter value: ") }

  answer <- readline(prompt = "Enter CLIENT_ID? y/n ")
  if(answer == "y") { CLIENT_ID <- readline(prompt = "Enter value: ") }

  rm(answer)
  VarsValues <- list(ls(), sapply(ls(), get, envir=environment())) 
  VarsValues
}

尝试打印函数中创建的所有对象时出错

1 个答案: