根据数据框列类型 R 对齐 xtable 列

Question

我在 knitr 中使用 xtable 创建表格，目前我左对齐所有 xtable 列，因为它简单且可重复。

但是，我想知道是否有一种方法可以根据数据框列中的数据类型（num、chr、int 等）对齐 xtable 列，以便我可以右对齐数字和左对齐字符。

谢谢！

Answer 1

我认为已经是这样了：来自 xtable 示例页面

 precip
             Mobile              Juneau             Phoenix         Little Rock         Los Angeles          Sacramento       San Francisco 
               67.0                54.7                 7.0                48.5                14.0                17.2                20.7 
             Denver            Hartford          Wilmington          Washington        Jacksonville               Miami             Atlanta 
               13.0                43.4                40.2                38.9                54.5                59.8                48.3 
           Honolulu               Boise             Chicago              Peoria        Indianapolis          Des Moines             Wichita 
               22.9                11.5                34.4                35.1                38.7                30.8                30.6 
         Louisville         New Orleans            Portland           Baltimore              Boston             Detroit    Sault Ste. Marie 
               43.1                56.8                40.8                41.8                42.5                31.0                31.7 
             Duluth Minneapolis/St Paul             Jackson         Kansas City            St Louis         Great Falls               Omaha 
               30.2                25.9                49.2                37.0                35.9                15.0                30.2 
               Reno             Concord       Atlantic City         Albuquerque              Albany             Buffalo            New York 
                7.2                36.2                45.5                 7.8                33.4                36.1                40.2 
          Charlotte             Raleigh             Bismark          Cincinnati           Cleveland            Columbus       Oklahoma City 
               42.7                42.5                16.2                39.0                35.0                37.0                31.4 
           Portland        Philadelphia           Pittsburg          Providence            Columbia         Sioux Falls             Memphis 
               37.6                39.9                36.2                42.8                46.4                24.7                49.1 
          Nashville              Dallas             El Paso             Houston      Salt Lake City          Burlington             Norfolk 
               46.0                35.9                 7.8                48.2                15.2                32.5                44.7 
           Richmond      Seattle Tacoma             Spokane          Charleston           Milwaukee            Cheyenne            San Juan 
               42.6                38.8                17.4                40.8                29.1                14.6                59.2 
> xalign(names(precip))# a character vector
[1] "l"
> xalign(precip)# a numeric
[1] "r