Help with table making in R

[sharmachetan]

How i can make a table from one column, having three coded variables to 3 columns with un-coded variable in RStudio. If anyone know some kind of code. I have 2 columns, sample and category, and column where 1 specify = weak, 2 = ok and 3 strong, but now i want a table with 3 columns of weak ok and strong with autofilling, like shown in image:

[mattsimmons]

Hey - here's a more general solution to what I think your problem is, using the tidyverse - it's probably not the most parsimonious, but I'm sure someone else could come up with a better one:

library(tidyverse)

df <- tibble(labels = LETTERS[1:10], 
             value = sample(1:3, 10, replace = TRUE))

df %>%
  mutate(n = 1) %>%
  pivot_wider(id_cols = c(labels), 
              names_from = c(value), 
              values_from = n, 
              values_fill = 0) %>%
  rename(weak = `1`, ok = `2`, strong = `3`)

[sharmachetan]

Thanks @mattsimmons. How i should use this code, like i tried but it shows some kind of error:

df <- read.csv("F:/cochransQ.csv", stringsAsFactors = F)
df %>%
  mutate(n = 1) %>%
  pivot_wider(id_cols = c(labels), 
              names_from = c(value), 
              values_from = n, 
              values_fill = 0) %>%
  rename(weak = `1`, ok = `2`, strong = `3`)
#> Error in df %>% mutate(n = 1) %>% pivot_wider(id_cols = c(labels), names_from = c(value), : could not find function "%>%"

^{Created on 2020-09-01 by the reprex package (v0.3.0)}

[williaml]

You need to load the tidyverse package (or at least magrittr) for the %>% function.

[elmstedt]

Since you already have some more modern code which is workable, I'll take a whack at it with a base R solution...

This is(by no means) the best, most readable, or extensible solution, but I have a penchant for single-command Base R solutions which take advantage of little know quirks in the language.

Let's imagine your data.frame is named df. Then,

set.seed(8675309)
df <- data.frame(product = letters, category = sample(3, 26, TRUE))
head(df)
  product category
1       a        3
2       b        2
3       c        3
4       d        1
5       e        3
6       f        1
 
df <- cbind(df,
            t(vapply(df[["category"]],
                     function(y) {
                       y == c(weak = 1, ok = 2, strong = 3)
                     },
                     integer(3))))
head(df)
  product category weak ok strong
1       a        3    0  0      1
2       b        2    0  1      0
3       c        3    0  0      1
4       d        1    1  0      0
5       e        3    0  0      1
6       f        1    1  0      0

[mattsimmons]

Nice!

Also: yes, to be clear, my code doesn’t use the same column names as the frame you provided, which elmstedt has helpfully done.

[sharmachetan]

Hello, I installed required tidyverse package but somehow its still not working:

library(RVAideMemoire)
#> Warning: package 'RVAideMemoire' was built under R version 4.0.2
#> *** Package RVAideMemoire v 0.9-77 ***
library(nonpar)
library(tidyverse)
#> Warning: package 'tibble' was built under R version 4.0.2
#> Warning: package 'tidyr' was built under R version 4.0.2
#> Warning: package 'dplyr' was built under R version 4.0.2
library(magrittr)
#> Warning: package 'magrittr' was built under R version 4.0.2
#> 
#> Attaching package: 'magrittr'
#> The following object is masked from 'package:purrr':
#> 
#>     set_names
#> The following object is masked from 'package:tidyr':
#> 
#>     extract
#> The following object is masked from 'package:RVAideMemoire':
#> 
#>     mod
df <- read.csv("F:/cochransQ.csv", stringsAsFactors = F)
colnames(df)[1] = "product"
df %>%
  mutate(n = 1) %>%
  pivot_wider(id_cols = c(labels), 
              names_from = c(value), 
              values_from = n, 
              values_fill = 0) %>%
  rename(weak = `1`, ok = `2`, strong = `3`)
#> Error: Can't subset columns that don't exist.
#> x Column `value` doesn't exist.

^{Created on 2020-09-02 by the reprex package (v0.3.0)}

[williaml]

See the error below:

#> Error: Can't subset columns that don't exist.
#> x Column `value` doesn't exist

What columns are in your cochransQ.csv"?

[mattsimmons]

Hey @sharmachetan - I've led you down a garden path. That's on me!
In your specific example, as given, it should be:

df %>%
  mutate(n = 1) %>%
  pivot_wider(id_cols = c(product), 
              names_from = c(category), 
              values_from = n, 
              values_fill = 0) %>%
  rename(weak = `1`, ok = `2`, strong = `3`)

See how I replaced 'label' with 'product', and 'value' with 'category'? Hopefully this gives you a clearer intuition as to what that bit of code is doing. You'll still have to do everything else, including loading the tidyverse package.