删除使用as.formula添加的空格

我从文本创建了一个公式，但结果公式包含不需要的空格。有没有办法防止这种情况

# text in which variables for formula are stored

mainEffectText ="age sex bmi cohort"
interactionText="age*cohort"

# get text into R

mainEffects <- read.table(textConnection(mainEffectText))
mainEffects <- t(mainEffects)
mainEffects <- as.character(mainEffects[,1])

interactions <- read.table(textConnection(interactionText))
interactions <- t(interactions)
interactions <- as.character(interactions[,1])


# put all terms into one vector
allTerms <- c(mainEffects,interactions)

# create formula
form <- as.formula(paste("Surv(time, event) ~ ",paste(allTerms, collapse=" +")))

---

空间不是一个真正的问题，但无论如何，请尝试以下方法：

# inputs
mainEffectText <- "age sex bmi cohort"
interactionText <- "age*cohort"
lhs <- "Surv(time, event)"

both <- paste(mainEffectText, interactionText)
paste0(gsub(" ", "", lhs), "~", gsub(" ", "+", both))

如果输入为这种形式（

lhs

如上所述），则使用：

# inputs
mainEffects <- c("age", "sex", "bmi", "cohort")
interactions <- "age*cohort"

both <- paste(paste(mainEffects, collapse = " "), 
              paste(interactions, collapse = " "))
paste0(gsub(" ", "", lhs), "~", gsub(" ", "+", both))

#输入
mainEffects为什么空格是一个问题？它是否过于可读？在运行回归时，空格似乎没有问题。我正在努力提高我对R的这些方面的理解。我尝试了一些不起作用的事情。我已经得到你的建议很多年了。当使用.formula时，空格仍然显示，对吗？是的，如果将其转换为公式并打印公式，则空格将显示。如果
s
是上面生成的字符串，则
fo
"Surv(time,event)~age+sex+bmi+cohort+age*cohort"

# inputs
mainEffects <- c("age", "sex", "bmi", "cohort")
interactions <- "age*cohort"

both <- paste(paste(mainEffects, collapse = " "), 
              paste(interactions, collapse = " "))
paste0(gsub(" ", "", lhs), "~", gsub(" ", "+", both))