Render loops

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10

# Render loops

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# <center>Render loops</center>

1

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# We loop together

```r
ratings <- readr::read_csv(here::here("data/ratings.csv"))

# the setup finds the individual series numbers
series <- sort(unique(ratings$series))

# the loop
for (this_series in series) {
  rmarkdown::render("01-bakeoff-report.Rmd",
         params = list(series = this_series))
}
```

This loop just overwrites the html file (check for the time run). Open file
`01-bakeoff-report.html` and you will see it says `Series 9`, the last series.

_psst...use the code in an R script to see each part_

???
The data loaded into the GitHub repository is split out by series as well as
altogether - `ratings.csv` was originally used in the advanced session.

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# <center>Loop v purrr</center>

Extending the loop to named files using `output_file = ` in either a loop or {purrr}

.pull-left[

```r

for (this_series in series) {
  rmarkdown::render(
    input = "01-bakeoff-report.Rmd",
    params = list(series = this_series), 
    output_format = "html_document", 
*   output_file = glue::glue("Report_for_Series_{this_series}"))
}

```
]

???
output_format() defaults to html but just for clarity this is included in the code.

.pull-right[

```r
purrr::map(
  .x = series,  # vector of param values
  .f = ~rmarkdown::render(
    input = "01-bakeoff-report.Rmd", 
    params = list(series = .x),  
    output_format = "word_document",
*   output_file = glue::glue("Report_for_Series", .x))
  )
)

```

]

Purr code adapted from [Matt Dray's blog](https://www.rostrum.blog/2020/03/12/knit-with-params/)

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