Conditional Cross tabulation in R

问题

Looking for the quickest way to achieve below task using "expss" package.

With a great package of "expss", we can easily do cross tabulation (which has other advantage and useful functions for cross-tabulations.), we can cross-tabulate multiple variables easily like below.

 #install.packages("expss")

 library("expss")
 data(mtcars)


  var1 <- "vs, am, gear, carb"
  var_names = trimws(unlist(strsplit(var1, split = ","))) 


  mtcars %>%
    tab_prepend_values %>%
    tab_cols(total(), ..[(var_names)]) %>%
    tab_cells(cyl) %>%
    tab_stat_cpct() %>%
    tab_pivot()

Above gives an output as: (column %)

                      #Total    vs          am          gear            carb                        
                                0     1     0     1     3     4   5     1   2    3   4    6    8 

  cyl             4    34.4   5.6  71.4  15.8  61.5   6.7  66.7  40  71.4  60                    
                  6    21.9  16.7  28.6  21.1  23.1  13.3  33.3  20  28.6           40  100      
                  8    43.8  77.8        63.2  15.4  80.0        40        40  100  60       100 
       #Total cases    32.0  18.0  14.0  19.0  13.0  15.0  12.0   5   7.0  10    3  10    1    1 

However, looking for an approach to create a table like below:

 CYL    |  VS = 0   |  AM = 1   |   Gear = 4 or Gear = 5    |  Carb (All)
   4        5.56        61.54               58.82                34.38
   6        16.67       23.08               29.41                21.88
   8        77.78       15.38               11.76                43.75

Total(col%) 100.00      100.00              100.00               100.00

Though i can achive this using dplyr and join functions but that is too complex incase we have to pass variables in runtime or dynamically.

Any help will be appriciable. Thanks!!

回答1:

You may try this:

1) Making a function which can create proportion out of the sum.

myprop_tbl <- function(x){
    return(round(x*100/sum(x),2))
}

2) Using purrr's map, applying the function on your data frame and then binding the result.

library(tidyverse)
tab <- mtcars %>% 
    group_by(cyl) %>% 
    summarise(vs_sum = sum(vs==0), am_sum = sum(am==1), 
              gear_sum = sum(gear == 4|gear==5), carb_sum= n())

finaltab <- bind_cols(tab[,1],map_df(tab[,2:length(tab)], myprop_tbl))

Output:

# * cyl vs_sum am_sum gear_sum carb_sum
#  <dbl>  <dbl>  <dbl>    <dbl>    <dbl>
#1  4.00   5.56   61.5     58.8     34.4
#2  6.00  16.7    23.1     29.4     21.9
#3  8.00  77.8    15.4     11.8     43.8**

EDIT:

After had a discussion with OP, it seems he also wanted to pass string of functions,

I am using here a package seplyr

tab <- mtcars %>% 
    group_by(cyl) %>% 
    summarise_se(c("vs_sum = sum(vs==0)",
              "am_sum = sum(am==1)",
              "gear_sum = sum(gear == 4|gear==5)", 
              "carb_sum = n()"))

It works also, but weired names you will get, to fix that you can do this:

This works perfectly as original answer which I have posted:

tab <- mtcars %>% 
    group_by(cyl) %>% 
    summarise_se(c("vs_sum" := "sum(vs==0)",
              "am_sum" := "sum(am==1)",
              "gear_sum" := "sum(gear == 4|gear==5)", 
              "carb_sum" := "n()"))

You may read this here @ this link

回答2:

Solution with orginal 'tab_*':

library("expss")
data(mtcars)
var_text = "vs_sum = vs==0, am_sum = am==1, gear_sum = gear == 4|gear==5, carb_sum = total(carb)"
var_expr = parse(text = sprintf("data.frame(%s)", var_text)) # parse text string to expression

var_list = calc(mtcars, 1*eval(var_expr)) %>% # caclulate data.frame with zero/one columns
    prepend_names() %>% # add names as labels
    mis_val(0) %>% # we don't need columns with FALSE condition
    set_val_lab(c("|" = 1)) # suppress values in table - we don't want to see TRUE/1

mtcars %>%
    tab_prepend_values %>%
    tab_cols(total(), var_list) %>%
    tab_cells(cyl) %>%
    tab_stat_cpct() %>%
    tab_pivot()

 # |     |              | #Total | vs_sum | am_sum | gear_sum | carb_sum  |
 # | --- | ------------ | ------ | ------ | ------ | -------- | --------- |
 # | cyl |            4 |   34.4 |    5.6 |   61.5 |     58.8 |      34.4 |
 # |     |            6 |   21.9 |   16.7 |   23.1 |     29.4 |      21.9 |
 # |     |            8 |   43.8 |   77.8 |   15.4 |     11.8 |      43.8 |
 # |     | #Total cases |   32.0 |   18.0 |   13.0 |     17.0 |      32.0 |

来源：https://stackoverflow.com/questions/50055988/conditional-cross-tabulation-in-r