Introduction to R Markdown

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# Introduction to R Markdown
## Dr. Mine Dogucu

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***R Markdown*** is a file format for making dynamic documents with R. An R Markdown document is written in markdown (an easy-to-write plain text format) and contains chunks of embedded R code.

***R Markdown*** files are the source code for rich, reproducible documents.

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.important[ You can transform an R Markdown file in two ways:
]

- knit - You can knit the file. The rmarkdown package will call the knitr package. knitr will run each chunk of R code in the document and append the results of the code to the document next to the code chunk.

- convert - You can convert the file. The rmarkdown package will use the pandoc program to transform the file into a new format. For example, you can convert your .Rmd file into an HTML, PDF, or Microsoft Word file.

---

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class: center middle

## Add Chunk

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## Run the Current Chunk

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## Knit

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<img src="img/chunk.png" width="90%" />

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##Inline Code
To embed R code in a line of text, surround the code with a pair of backticks and the letter r, like this.

- Two plus two equals 4.

<img src="img/rmd-inline.png" width="90%" />
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# Inline Code Example

``` r
cyl_prcnt <-
  mtcars %>% 
  count(cyl) %>% 
  mutate(prcnt = n/sum(n)*100) %>%
  filter(cyl == 4) %>%
  select(prcnt)
```

`$$\\[0.05in]$$`

**34.375** percent of cars in our dataset have 4 cylinders.

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class: middle center

## Shortcuts

|                            | Windows          | Mac              |
|----------------------------|------------------|------------------|
| add chunk                  | Ctrl + Alt + I   | Cmd + Option + I |
| run the current chunk      | Ctrl + Alt + C   | Cmd + Option + C |
| run current line/selection | Ctrl + Enter     | Cmd + Return     |
| knit                       | Ctrl + Shift + K | Cmd + Shift + K  |

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## Summary of our Tools

**R** is a programming language used mainly for statistical computing.

**markdown** is a markup language for creating formatted text.

**R Markdown** is a file format that can handle R and markdown (and many other languages).

**RStudio** is an integrated development environment (IDE).

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## R vs. RStudio

- You can write English (a language, so is R) words in a notebook (like RStudio).  
- But you can also write it elsewhere too (on a napkin, sand etc. or even in different notebooks).   
- R is a language that can be written in many different places, RStudio is just one of them.   
- There are many others.