如何摆脱输出中的列表位置/行号

Question

我想显示一个函数的许多结果，但我读到你只能返回一个对象，因此如果你想显示更多，就必须使用一个列表。这工作正常，但有时输出不是很可读（在这个假例子中，它并不算太糟糕，但在我的工作中是这样）。如何摆脱或抑制 R 自动添加到我的输出中的这些行/列表位置？

当前输出：

[[1]]
[1] "There are 5 total observations"

[[2]]
[1] "The mean of these observations is 0.564422113896047"

[[3]]
[1] "The observations are shown below:"

[[4]]
[1]  1.0496648  0.4807251  0.8536269  1.7946839 -1.3565901

期望的输出：

"There are 5 total observations"


"The mean of these observations is 0.564422113896047"


"The observations are shown below:"


 1.0496648  0.4807251  0.8536269  1.7946839 -1.3565901

我很高兴能够移除每行上方的双括号输出，但保留行号输出。如果我还可以更改各个点的行距，那会更好，但并不是真正需要的。

用于创建此函数/输出的代码：

test <- function(n_observations) {

  obs <- rnorm(n_observations)

return(list(
  paste0("There are ",n_observations," total observations"),
  paste0("The mean of these observations is ",mean(obs)),
  paste0("The observations are shown below:"),
  obs
))

}

test(n_observations = 5)

编辑： Ronaks 的回答在这种情况下工作得很好，因为我在这个例子中没有包含列表/数据框。我已经更新了下面的函数，以显示您在使用一个礼物时遇到的错误，即；

 test <- function(n_observations) {

  obs <- rnorm(n_observations)
  random_table <- as.data.frame(cbind(c(1:n_observations), obs))

return(cat(
  paste0("There are ",n_observations," total observations\n"),
  paste("\n"),
  paste0("The mean of these observations is ",mean(obs),"\n"),
  paste0("The observations are shown below:\n"),
  obs,
  random_table
  ))
}

test(n_observations = 5)

输出（和错误）：

There are 5 total observations

 The mean of these observations is 0.445438123798109
 The observations are shown below:
 1.677665 1.379066 0.3436419 0.4783038 -1.651487 Error in cat(paste0("There are ", n_observations, " total observations\n"),  : 
  argument 6 (type 'list') cannot be handled by 'cat'

Answer 1

如果您想改进输出的打印方式，我们可以使用cat，包括每行后的“\n”以在不同的行中显示输出。

test <- function(n_observations) {
   obs <- rnorm(n_observations)

   return(cat(
     paste0("There are ",n_observations," total observations\n"),
     paste0("The mean of these observations is ",mean(obs), "\n"),
     paste0("The observations are shown below:\n"),
     obs
   ))
}

test(n_observations = 5)

#There are 5 total observations
# The mean of these observations is -0.785794194405614
# The observations are shown below:
# -0.4806757 -0.6366636 0.3147989 -1.873661 -1.25277

---

编辑

如果我们只想显示结果为什么要进入returning 他们，我们可以从函数本身打印它们。

test <- function(n_observations) {

  obs <- rnorm(n_observations)
  random_table <- as.data.frame(cbind(c(1:n_observations), obs))


  cat(paste0("There are ",n_observations," total observations\n"),
  paste0("The mean of these observations is ",mean(obs), "\n"),
  paste0("The observations are shown below:\n"),
  obs, "\n\n The table is as below : \n\n")
  print(random_table)
}

test(n_observations = 5)

#There are 5 total observations
# The mean of these observations is 0.540141211615552
# The observations are shown below:
# 1.922104 -0.5334201 -0.9881913 1.838563 0.4616504 

# The table is as below : 

#  V1        obs
#1  1  1.9221042
#2  2 -0.5334201
#3  3 -0.9881913
#4  4  1.8385628
#5  5  0.4616504

可以避免最后一个print(random_table)，我们只能使用random_table，但我假设OP对print有很多其他类似的东西，所以在这种情况下它可能很有用。