Review

Motivation

Markdown

RMarkdown

Representational State Transfer APIs

Exposes data components

Transfer data with HTTP (typically)

Facilitates web-queries of content

Navigate to a URL

Return information (JavaScript Object Notation)

https://api.spotify.com/v1/search?q=adele&type=artist

{
    artists: {
        href: "https://api.spotify.com/v1/searc...",
        items: [{
            external_urls: {
            spotify: "https://open.spotify...."
        },
        followers: {
            href: null,
            total: 4093432
        },
    }
}

How many numbers are there in this summary?

Hundreds of values

Dozens of graphics

ctrl + c

ctrl + v

ctrl + v

ctrl + v

ctrl + v

Dynamically generate documents

Integrate code and reporting

Include results in text

Incorporate graphics

# Markdown Description
Allows you to apply simple syntax to create 
well formatted documents, including the ability to:

- Make text **bold**, *italicized*, or `monospace`
- Have headers
- Create lists
	1.  Ordered lists
	2. Or unordered lists 

This is the code we will look 
at in class.  This is just 
plain  old Markdown that 
lets you render text in
**bold** or _italics_.
However, we can put in a
chunk or R code, and it
will show us the code 
and results!

```{r}
# Write R code in here
# It's wrapped in three ```
x <- runif(1:100)
hist(x)
```

Click Knit HTML

file.Rmd

file.html

This is the code we will look 
at in class.  This is just 
plain  old Markdown that 
lets you render text in
**bold** or _italics_.
However, we can put in a
chunk or R code, and it
will show us the code 
and results!

```{r}
x <- runif(1:100)
hist(x)
```

This is the code we will look 
at in class.  This is just 
plain  old Markdown that 
lets you render text in
**bold** or _italics_.
However, we can put in a
chunk or R code, and it
will show us the code 
and results!

```{r, eval=FALSE}
x <- runif(1:100)
hist(x)
```
(It did not show the plot)

eval=FALSE

This is the code we will look 
at in class.  This is just 
plain  old Markdown that 
lets you render text in
**bold** or _italics_.
However, we can put in a
chunk or R code, and it
will show us the code 
and results!

```{r, echo=FALSE}
x <- runif(1:100)
hist(x)
```
(It did not show the **code**)

echo=FALSE

Hide results (i.e., don't evaluate code)

Hide code (i.e., don't echo it)

Hide warnings

Hide messages (hint, hint)

```{r, eval=FALSE}
# R code goes here
```

```{r, echo=FALSE}
# R code goes here
```

```{r, warning=FALSE}
# R code goes here
```

```{r, message=FALSE}
# R code goes here
```

Reference R variables/values within Markdown text!

# Markdown text
I wrote some markdown text, then did some analysis:
```{r}
scores <- runif(100, 50, 100)
avg <- mean(scores)
```
Then I wanted to tell you that the average was `r avg` across
 `r length(scores)` tests.

RMarkdown website

RMarkdown cheatsheet

RMarkdown book!

Assignment-5: Github Report (due Wed. 2/10)