{epoxy}

super glue for data-driven reports and Shiny apps

Garrick Aden-Buie

posit::conf(2023)

Infant day care costs

up to $15,417 a year

I want to share a interesting fact I read recently. Did you know that…

Your first thought is probably, “woah, children are expensive!” And as a parent, I can say. Yeah, you’re right.

But also as a parent, I know that this isn’t just a boring statistic from an executive report. Behind this number are real conversations I’ve had with my partner as we figure out how we’ll care for our children and provide for them too.

As a data scientist, though, I bet we’re all wondering “how did that number get there?” Is that an average or a mean? Where did the data come from exactly? (It’s from the US Dept. of Labor’s National Database of Childcare Price, by the way.)

As someone who’s spent a lot of time working on reporting tools for data scientists, I really mean it. Like “how exactly did that number get there?”

Infant day care costs

up to 

Infant day care costs

up to

$15,417

a year

report.Rmd

```{r}
max_med_cost <-
  childcare_costs |>
  # group and summarize… |>
  filter(cost = max(cost)) |>
  pull(cost)  
```

Infant day care costs

up to 

 

report.Rmd

```{r}
max_med_cost <-
  childcare_costs |>
  # group and summarize… |>
  filter(cost = max(cost)) |>
  pull(cost)  
```

Infant day care costs

up to

`r max_med_cost`

a year.

This is the promise and magic of R Markdown.

• prose in same document as code
• reproducible writing
• update data or analysis and re-render
• output changes!

When rendered, max median cost is woven into the prose…

Report: Childcare Costs

Infant day care costs

up to 1.541696^{4}

a year.

Report: Childcare Costs

Infant day care costs

up to $15,416

a year.

• Inline syntax
• Just-in-time formatting
• Reusable templates

• Made for developers
• Very light-weight
• Files that end in .R

• Made for data scientists
• Using familiar packages
• Scripts, reports, apps

• effective communication
• without taking you out of the flow of writing

 
Infant day care costs
up to `r max_med_cost`
a year.
 

```{epoxy}
Infant day care costs
up to `r max_med_cost`
a year.
```

```{epoxy}
Infant day care costs
up to `r max_med_cost`
a year.
```

```{epoxy}
Infant day care costs
up to {max_med_cost}
a year.
```

```{epoxy}
Infant day care costs
up to {.dollar max_med_cost}
a year.
```

Infant day care costs

up to $15,417 a year

glue(
  "{max_med_cost}"
)
#> 15416.96

glue(
  "{max_med_cost}",
  .transformer = identity_transformer
)
#> 15416.96

glue(
  "{max_med_cost}",
  .transformer = epoxy_transform_inline()
)
#> 15416.96

glue(
  "{.dollar max_med_cost}",
  .transformer = epoxy_transform_inline()
)
#> $15,416.96

epoxy("{.dollar max_med_cost}")
#> $15,416.96

Inline epoxy transformers

{.dollar max_med_cost} 1.541696^{4} $15,416.96

{.percent mhi_pct} 0.2376447 24%

{.comma county_pop_med} 1.595192^{6} 1,595,192

{.ordinal cost_rank} 1 1st

{.titlecase age} infant Infant

{.bold county_size} very large very large

{.italic type} day care day care

```{epoxy cost-summary}
{.titlecase age} {.italic type}
in {.bold county_size} counties
ranks {.ordinal cost_rank} in childcare costs
at {.dollar max_med_cost} per year,
or {.percent mhi_pct} of median household income.
```

Infant day care in very large counties ranks 1st in childcare costs at $15,416.96 per year, or 24% of median household income.

Write out a full sentence using these variables in an epoxy chunk.

These inline transformers are just little tiny functions. Let’s write our own…

epoxy_transform_set(
  .cpm = function(x) x / 12
)

```{epoxy cost-summary}
{.titlecase age} {.italic type}
in {.bold county_size} counties
ranks {.ordinal cost_rank} in childcare costs
at {.dollar max_med_cost} per year,
about {.cpm max_med_cost} per monthabout {.dollar {.cpm max_med_cost}} per month
or {.percent mhi_pct} of median household income.
```

Infant day care in very large counties ranks 1st in childcare costs at $15,416.96 per year, about 1284.75 per month about $1,284.75 per month or 24% of median household income.

epoxy_transform_set(
  .cpm = function(x) x / 12,
  .dollar = scales::label_dollar(),
  .percent = scales::label_percent()
)

Infant day care in very large counties ranks 1st in childcare costs at $15,416.96 per year, about $1,284.75 per month or 24% of median household income.

epoxy_transform_set(
  .cpm = function(x) x / 12,
  .dollar = scales::label_dollar(accuracy = 100),
  .percent = scales::label_percent(accuracy = 0.1)
)

Infant day care in very large counties ranks 1st in childcare costs at $15,400 per year, about $1,300 per month or 23.8% of median household income.

childcare_summary
#> # A tibble: 10 × 9
#>    cost_rank county_size type      age        max_med_cost mhi_2018 county_pop_med n_counties mhi_pct
#>        <int> <chr>       <chr>     <chr>             <dbl>    <dbl>          <dbl>      <int>   <dbl>
#>  1         1 very large  day care  infant           15417.    64874        1595192         37   0.238
#>  2         2 large       day care  infant           13420.    68021         703619         77   0.197
#>  3         3 very large  day care  toddler          12121.    64874        1595192         37   0.187
#>  4         4 large       day care  toddler          11180     68021         703619         77   0.164
#>  5         5 very large  day care  preschool        11050     64874        1595192         37   0.170
#>  6         6 mid-sized   day care  infant           10194.    58775         179085        353   0.173
#>  7         7 large       day care  preschool        10078.    68021         703619         77   0.148
#>  8         8 very large  home care infant            9892.    64874        1595192         37   0.152
#>  9         9 very large  day care  school-age        9199.    64874        1595192         37   0.142
#> 10        10 very large  home care toddler           9100     64874        1595192         37   0.140

```{epoxy cost-summary, .data = childcare_summary[1, ]}
{.titlecase age} {.italic type}
in {.bold county_size} counties
ranks {.ordinal cost_rank} in childcare costs
at {.dollar max_med_cost} per year,
about {.dollar {.cpm max_med_cost}} per month
or {.percent mhi_pct} of median household income.
```

Infant day care in very large counties ranks 1st in childcare costs at $15,400 per year, about $1,300 per month or 23.8% of median household income.

Update the epoxy chunk to use the .data argument and the first row of childcare_summary (these are the values)

```{epoxy cost-summary, .data = childcare_summary[8, ]}
{.titlecase age} {.italic type}
in {.bold county_size} counties
ranks {.ordinal cost_rank} in childcare costs
at {.dollar max_med_cost} per year,
about {.dollar {.cpm max_med_cost}} per month
or {.percent mhi_pct} of median household income.
```

Infant home care in very large counties ranks 8th in childcare costs at $9,900 per year, about $800 per month or 15.2% of median household income.

then swap out for the 8th row which effectively compares day care to home care

childcare_summary |>
  dplyr::filter(
    age == "infant",
    type == "home care",
    county_size == "very large"
  ) |>
  epoxy_use_chunk(label = "cost-summary")

Infant home care in very large counties ranks 8th in childcare costs at $9,900 per year, or 15.2% of median household income.

report-html.Rmd

```{epoxy_htmlepoxy_html}
in {{@bold county_size}}{{@bold county_size}} counties
```

in <strong><strong>very large</strong></strong> counties

report-latex.Rmd

```{epoxy_latexepoxy_latex}
in <<.bold county_size>><<.bold county_size>> counties
```

in \textbf{very large} counties

R Console

epoxy("{.dollar {.cpm max_med_cost}} per month")
#> $1,300 per month

epoxy_html("{{@dollar {{@cpm max_med_cost }} }} per month")
#> $1,300 per month

epoxy_latex("<<.dollar <<.cpm max_med_cost>> >> per month")
#> $1,300 per month

epoxy_use_file(file = "cpm-snippet.md")
#> $1,300 per month

• {epoxy} in Reports
  • R Markdown and Quarto
  • Markdown, HTML, or LaTeX
• {epoxy} in scripts
  • epoxy()
  • epoxy_html()
  • epoxy_latex()

Shiny

library(shiny)
library(bslib)

ui <- page_fixed(
  textInput("greetings", "Greeting", "Hello"),
  textInput("company", "Company", "rstudio"),
  textInput("year", "Year", "2023"),
  ui_epoxy_html(
    .id = "hello",
    p(
      "{{greetings}}, {{company}}::conf({{year}})!"
    )
  )
)

server <- function(input, output, session) {
  output$hello <- render_epoxy(
    greetings = input$greetings,
    company = input$company,
    year = input$year
  )
}

shinyApp(ui, server)

• Blend data and prose

• Reusable templates

• Just-in-time formatting

• Reports, scripts and apps

pkg.garrickadenbuie.com/epoxy

grrrck@fosstodon.org