Table output like console

[mpickard]

I'm writing a tutorial for my students to demonstrate what group_by() does. I want to highlight the fact that it doesn't do anything that is visible to the tibble except denote the grouping variable.Like this:

# A tibble: 32 x 11
# Groups:   cyl [3]
     mpg   cyl  disp    hp  drat    wt  qsec    vs    am  gear  carb
   <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
 1  21       6  160    110  3.9   2.62  16.5     0     1     4     4
 2  21       6  160    110  3.9   2.88  17.0     0     1     4     4

However, rmarkdown (I'm using the learnr package, but don't think it should matter) renders the table nicely and eliminates the header portion. How do I get that header portion to display in the rmarkdown output? I thought the results='asis' option would do the trick, but it has no effect. Any help would be appreciated.

Thanks in advance.

Matt

[technocrat]

There are a couple of things to try:

1.In the chunk, set echo = TRUE
2.If you saved the output grouped <- ungrouped %>% group_by(var) %>% [further] then if you inline

`r grouped`

You'll get the output you want. The first option prepends dual hashtags ##

[mpickard]

That's how I want my output to show up in my output file. But it's getting formattted as a nice table, something under the good is changing the format. The only difference is that my header is like this because I'm using learnr.

---
title: "Data Wrangling in R"
output: learnr::tutorial
runtime: shiny_prerendered
---

I didn't think that would make a difference.

[mpickard]

Thanks, technocrat.

I was already using the echo=TRUE option and I didn't see any difference with the second suggestion. I'm now wondering if learnr or shiny is doing something in the background. Here's what I see in my output file:

[technocrat]

Sorry to be obscure. Try this

library(tidyverse)
#> Registered S3 methods overwritten by 'ggplot2':
#>   method         from 
#>   [.quosures     rlang
#>   c.quosures     rlang
#>   print.quosures rlang
#> Registered S3 method overwritten by 'rvest':
#>   method            from
#>   read_xml.response xml2
out <-  mtcars %>% group_by(cyl)
as_tibble(out)
#> # A tibble: 32 x 11
#>      mpg   cyl  disp    hp  drat    wt  qsec    vs    am  gear  carb
#>  * <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
#>  1  21       6  160    110  3.9   2.62  16.5     0     1     4     4
#>  2  21       6  160    110  3.9   2.88  17.0     0     1     4     4
#>  3  22.8     4  108     93  3.85  2.32  18.6     1     1     4     1
#>  4  21.4     6  258    110  3.08  3.22  19.4     1     0     3     1
#>  5  18.7     8  360    175  3.15  3.44  17.0     0     0     3     2
#>  6  18.1     6  225    105  2.76  3.46  20.2     1     0     3     1
#>  7  14.3     8  360    245  3.21  3.57  15.8     0     0     3     4
#>  8  24.4     4  147.    62  3.69  3.19  20       1     0     4     2
#>  9  22.8     4  141.    95  3.92  3.15  22.9     1     0     4     2
#> 10  19.2     6  168.   123  3.92  3.44  18.3     1     0     4     4
#> # … with 22 more rows

^{Created on 2019-05-15 by the reprex package (v0.2.1)}

[technocrat]

Enclosed in

```{r}
library(tidyverse)
out <-  mtcars %>% group_by(cyl)
as_tibble(out)

(assuming tidyverse isn't already in your namespace)

[technocrat]

I neglected to go back to the top post. group_by doesn't do anything unless you %>% it to count or summarize other than to indicate that the grouping attribute has been set

[grrrck]

As mentioned in my reply in a similar question, to control the output format of tables in learnr tutorials — to show the tibble as it would be printed in the console, for example — you can set the df_print option in the YAML frontmatter:

---
output:
  learnr::tutorial:
    df_print: default # the learnr default is "paged"
---