首页 文章

使用dplyr和tidyr制作更复杂的表格

提问于
浏览
2

我有一个看起来像这样的数据集,虽然真实的例子有更多的列 . 只有一行(目前) .

Results <- structure(list(PCV2_CT_Min = 7.15, PPV2_CT_Min = 11.4, PPV3_CT_Min = 8.6, 
PPV4_CT_Min = 16.3, PPV_CT_Min = 29.58, NI_BOCA_CT_Min = 20.51, 
SW_BOCA_CT_Min = 23.49, PCV2_CT_Count = 695L, PPV2_CT_Count = 695L, 
PPV3_CT_Count = 695L, PPV4_CT_Count = 695L, PPV_CT_Count = 695L, 
NI_BOCA_CT_Count = 695L, SW_BOCA_CT_Count = 695L),
.Names = c("PCV2_CT_Min", "PPV2_CT_Min", "PPV3_CT_Min", "PPV4_CT_Min", "PPV_CT_Min", "NI_BOCA_CT_Min", "SW_BOCA_CT_Min", "PCV2_CT_Count", "PPV2_CT_Count", "PPV3_CT_Count", "PPV4_CT_Count", "PPV_CT_Count", "NI_BOCA_CT_Count", "SW_BOCA_CT_Count"),
row.names = c(NA, -1L), class = c("tbl_df", "tbl", "data.frame"))

每个列名称由变量名称和函数名称组成,因此PCV2_CT_Min是PCV2病毒测试的最小计数(CT); PCV_CT_Count是测试动物的总数,依此类推 .

它是通过在另一个数据集上运行来自dplyr的summarize_all,对猪进行单独的病毒测试,使用更长版本的代码:

V <- Pig %>%
     select(ends_with('CT')) %>% 
     summarise_all(funs(Min = min(.,na.rm=TRUE),
     Count = n()))

在实际的例子中,有更多的函数,它们采用不同的参数 . 我想最终得到的是这样的数据帧: -

Parameter PCV_CT PPV2_CT PPV3_CT PPV4_CT PPV_CT NI_BOCA_CT SW_BOCA_CT
Min       7.15   11.4    8.6     16.3    29.58  20.51     23.49
Count     695    695     695     695     695    695       695

我曾经想过有一种简单的方法可以做到这一点,也许使用类似于tidyr的单独命令,但是我绞尽脑汁,搜索SO,以及更广泛的网络,并查看了tidyr文档,但都无济于事 . 我认为答案应该是显而易见的,但我看不出来 .

我将不胜感激任何和所有的帮助 .

2 回答

  • 3

    您需要 gather 所有列, separate 将您想要的相关名称中的名称,然后 spread 将数据恢复为宽格式:

    library(tidyverse)
    Results %>% 
      gather(var, val, everything()) %>% 
      extract(var, into = c("var", "measure"), regex = "(.*)_(Min|Count)") %>% 
      spread(var, val)
    # # A tibble: 2 x 8
    #   measure NI_BOCA_CT PCV2_CT PPV_CT PPV2_CT PPV3_CT PPV4_CT SW_BOCA_CT
    # *   <chr>      <dbl>   <dbl>  <dbl>   <dbl>   <dbl>   <dbl>      <dbl>
    # 1   Count     695.00  695.00 695.00   695.0   695.0   695.0     695.00
    # 2     Min      20.51    7.15  29.58    11.4     8.6    16.3      23.49
    

    要分割的更一般的正则表达式可能是 regex = "(.*)_(.*)" ,如果您使用了多个其他摘要函数,这可能很有用 .


    我知道您有理由以这种形式提供您的数据,但这与您实际应该看到的内容有点相反 . 理想情况下,让您的列包含所有相同类型度量的数据更有意义....

  • 1

    使用基础R / reshape2 的两个不同想法可能是:

    Split and stack:

    dfs <- lapply(c("Min", "Count"), function(x) {
            res <- Results[, grepl(x, names(Results))]
            res <- setNames(res, gsub(paste0("_", x), "", names(res)))
            res$measure <- x
            return(res)
          })
    do.call(rbind, dfs)
    
    # A tibble: 2 x 8
    #  PCV2_CT PPV2_CT PPV3_CT PPV4_CT PPV_CT NI_BOCA_CT SW_BOCA_CT measure
    #    <dbl>   <dbl>   <dbl>   <dbl>  <dbl>      <dbl>      <dbl>   <chr>
    #1    7.15    11.4     8.6    16.3  29.58      20.51      23.49     Min
    #2  695.00   695.0   695.0   695.0 695.00     695.00     695.00   Count
    

    Melt and dcast:

    library(reshape2)
    melted <- melt(data.frame(Results))
    melted$measure <- gsub(".*_(Min|Count)", "\\1", melted$variable)
    melted$variable <- gsub("_(Min|Count)", "", melted$variable)
    dcast(melted, measure ~ variable)
    
    #  measure NI_BOCA_CT PCV2_CT PPV_CT PPV2_CT PPV3_CT PPV4_CT SW_BOCA_CT
    #1   Count     695.00  695.00 695.00   695.0   695.0   695.0     695.00
    #2     Min      20.51    7.15  29.58    11.4     8.6    16.3      23.49
    

相关问题