如何用文本而不是表达式来提供 deparse 解析序列？ ipwpoint函数的分母入口

Question

我在使用 ipw 包中的 ipwpoint 函数时遇到问题。这是一个函数 ipwpoint:

的工作示例

library(ipw)
df <- data.frame(ttt = sample(0:1,500,replace = T),
                 cofounder1 = rnorm(500),
                 cofounder2 = rnorm(500))

ipwt <- ipwpoint(
  exposure = ttt ,
  family = "binomial",
  link = "logit",
  numerator = ~ 1,
  denominator = ~cofounder1 + cofounder2 ,
  data = df
)

现在假设我想定义相同的回归，但分母来自变量名称的向量

vars <- c("cofounder1","cofounder2")

我想我可以使用一个公式：

formula <- as.formula(paste0("~",paste0(vars,collapse = "+")))
ipwt <- ipwpoint(
  exposure = ttt ,
  family = "binomial",
  link = "logit",
  numerator = ~ 1,
  denominator = formula,
  data = df
)

但这不起作用：

Error in eval(parse(text = paste(deparse(tempcall$exposure, width.cutoff = 500), : object 'tttformula' not found

因为该函数所做的是解析一个表达式，然后将其粘贴到 exposure，然后再次解析并计算它，请参阅 https://github.com/cran/ipw/blob/master/R/ipwpoint.R#L87。所以它粘贴了“公式”而不是实际的公式。

使用文字也不行：

ipwt <- ipwpoint(
  exposure = ttt ,
  family = "binomial",
  link = "logit",
  numerator = ~ 1,
  denominator = paste0("~",paste0(vars,collapse = "+")),
  data = df
)

如何从 c("cofounder1","cofounder2") 向量定义回归？

Answer 1

如何将整个函数调用解析为字符串？:

function_call<-paste0("ipwt <- ipwpoint(
  exposure = ttt ,
  family = \"binomial\",
  link = \"logit\",
  numerator = ~ 1,
  denominator = ~",vars[1]," + ",vars[2]," ,
  data = df
)")

eval(parse(text = function_call))

如何用文本而不是表达式来提供 deparse 解析序列？ ipwpoint函数的分母入口

how to feed a deparse parse sequence with text instead of expression ? denominator entry of ipwpoint function

parsing

regression

r