如何使用 print 或 cat 缩进摘要等多行输出的输出，并保持列对齐？

Question

这个问题可能概括为打印任何类型的多行输出，并保持列对齐。我的实际问题涉及 summary.default.

的输出

我正在尝试将 2 的倍数的缩进添加到 summary.default 函数的 cat 输出中。我用cat和print做了一些尝试，也参考了一些相关的答案，但到目前为止都失败了。

f <- function(x) {
  s <- summary.default(x)
  liner <- Reduce(paste0, rep("-", 70))
  cat("\n", liner, "\n")  ## ATT 1. -------------------------------
  cat("\n", "foo first attempt", "\n")
  cat("\n--|\n")
  
  print(round(s, 3))  #
  
  cat("\n----|\n")
  cat("\n    *additional information\n")
  cat("\n", liner, "\n")  ## ATT 2. -------------------------------
  cat("\n", "foo second attempt", "\n")
  cat("\n--|\n")
  
  print(unname(as.data.frame(cbind("   ", t(attr(s, "names"))))), row.names=F)  #
  print(unname(as.data.frame(cbind(" ", t(round(unclass(s), 3))))), row.names=F)  #
  
  cat("\n----|\n")
  cat("\n    *additional information\n")
  cat("\n", liner, "\n")  ## ATT 3. -------------------------------
  cat("\n", "foo third attempt", "\n")
  cat("\n--|\n")
  cat("\n  ", attr(s, "names"), "\n")
  
  cat("\n  ", round(s, 3), "\n")  #
  
  cat("\n----|\n")
  cat("\n    *additional information\n")
}

> x <- rnorm(100)
> f(x)

---------------------------------------------------------------------- 

 foo first attempt 

--|
   Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
 -2.069  -0.654  -0.092  -0.075   0.696   1.997 

----|

    *additional information

 ---------------------------------------------------------------------- 

 foo second attempt 

--|
                                          
     Min. 1st Qu. Median Mean 3rd Qu. Max.
                                          
   -2.069 -0.654 -0.092 -0.075 0.696 1.997

----|

    *additional information

 ---------------------------------------------------------------------- 

 foo third attempt 

--|

   Min. 1st Qu. Median Mean 3rd Qu. Max. 

   -2.069 -0.654 -0.092 -0.075 0.696 1.997 

----|

    *additional information

---| 表示所需的缩进。 第一次尝试 没有任何缩进。 第二次尝试 更好，但行与行之间还有额外的 space，并且在四舍五入到不同数字时不能概括。在 尝试 3 时，列不再对齐。

如何使用 R 附带的功能获得所需的输出？

期望的输出：

---------------------------------------------------------------------- 
  
foo some text 

    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
  -2.069  -0.654  -0.092  -0.075   0.696   1.997 
      
    *additional information

Answer 1

我唯一能想到的就是手动重新assemble 'summary' 输出以说明不同的 'cell' 宽度：

add_indent_and_right_align <- function(summry, indent=2, minDist= 2, rounding = 3) {
  # add an indent and then right-align summary output table
  #
  # summry - summary object
  # indent - integer Number of spaces to add before summary output
  # minDist . integer Minimal number of spaces between two columns
  # rounding - integer Number of decimals to round summary to

  header <- attr(summry, "names")
  value <- round(summry, 3)     
  r = list()
  for (i in seq_along(header)) {
    # find out how wide the column has to be
    # to fit header and value and indent (if first column) or minDist
    #
    max_len <- max(nchar(header[i]), nchar(value[i]))       
    if (i == 1) {
      cell_width <- max_len + indent
      r[1] <- paste0(paste0(rep(" ", cell_width - nchar(header[i])), collapse=""), header[i])
      r[2] <- paste0(paste0(rep(" ", cell_width - nchar(value[i])), collapse=""), value[i])
    } else {
      cell_width <- max_len + minDist
      r[1] <- paste0(r[1], paste0(rep(" ", cell_width - nchar(header[i])), collapse=""), header[i])
      r[2] <- paste0(r[2], paste0(rep(" ", cell_width - nchar(value[i])), collapse=""), value[i])
    }
  }
  return(paste0(r, collapse="\n"))
}

f <- function(x) {
  indent <- 4 # how many spaces shoud the whole summary output be indented?
  s <- summary.default(x)

  cat(paste0(rep("-", 70), collapse=""), "\n")
  cat("\n")
  cat("foo some text", "\n")
  cat("\n")
  cat(add_indent_and_right_align(summry=s, indent=4, minDist= 1, rounding = 3), "\n")
  cat("\n")
  cat(paste0(paste0(rep(" ", indent), collapse=""), "*additional information"), "\n")
  cat("\n")
}

set.seed(1)
x <- rnorm(100)
f(x)

Returns:

---------------------------------------------------------------------- 

foo some text

    Min. 1st Qu. Median  Mean 3rd Qu.  Max.
  -2.215  -0.494  0.114 0.109   0.692 2.402

  *additional information

Answer 2

对于此任务，您可以连续使用 base r 的两个函数。有一个函数 capture.output 可以捕获像 print 这样的命令的输出。使用 paste 组合所需数量的空格，可以将其写入标准输出 writelines，从而保留数据帧打印输出的行结构。要执行上述操作，请将打印输出中给出的所有信息作为示例合并到 data.frame (df).

df = data.frame("Min."=-2.069, "First Qu."= -0.654,  "Median"= -0.092   , "Mean"  =-0.075, "Third Qu."=  0.696,    "Max."=  1.997 )
writeLines(paste0("  ", capture.output(print(df, row.names = F))))

我添加了 roe.names = F，以禁止打印数据帧的行号

如何使用 print 或 cat 缩进摘要等多行输出的输出，并保持列对齐？

How to indent output of multiline-outputs such as summary, using print or cat, and keep columns aligned?

r

printing

indentation

cat

summary

期望的输出：