r - pander 小数点后的位数

Question

我正在尝试使用 .rmd 文件中的 pander 将表格输出为小数点后有 2 位数字的 pdf，但我使用以下 rmd 没有得到任何数字:

---
title: "Long table test"
output: pdf_document
---

Here is a table:

```{r setup}
library (data.table)
library (pander)

set.seed(1984)
longString <- "description string"
dt <- data.table(id=c(1:3),description=rep(longString,3),value=rnorm(3,mean=10000,sd=1))
```

```{r pander-table}
panderOptions('round',2)
panderOptions('digits',2)
panderOptions('keep.trailing.zeros',TRUE)
pander(dt, split.cell = 80, split.table = Inf)
```

结果

-------------------------------
 id     description      value 
---- ------------------ -------
 1   description string  10000 

 2   description string  10000 

 3   description string  10001 
-------------------------------

想看看

----------------------------------
 id     description      value 
---- ------------------ ----------
 1   description string  10000.41 

 2   description string   9999.68 

 3   description string  10000.64 
----------------------------------

Answer 1

设置 round 对数字的数量没有任何直接影响(尽管由于可能使数字变得无关紧要 (0) 而产生一些间接影响)。这里的主要问题是 pander 不允许您设置 format() 的 nsmall 参数，这将设置

the minimum number of digits to the right of the decimal point in formatting real/complex numbers in non-scientific formats. Allowed values are 0 <= nsmall <= 20.

但由于 pander 仅将数值提供给 format()，您可以通过将值 as.character() 提供给 pander 来简单地解决此问题:

library (data.table)
library(magrittr)
library (pander)

set.seed(1984)
longString <- "description string"
dt <- data.table(id = c(1:3),
                 description = rep(longString, 3),
                 value = rnorm(3, mean = 10000, sd = 1))

pander(
  x = dt %>% mutate(value = value %>% round(2) %>% as.character()),
  split.cell = 80,
  split.table = Inf,
  justify = "ccr"
)

结果是:

------------------------------------
 id      description           value
---- -------------------- ----------
 1    description string    10000.41

 2    description string     9999.68

 3    description string    10000.64
------------------------------------