Introduction to the Patchwork Package

# Introduction to the Patchwork Package
## Scaffolding for Composite Figures and Infographics
### Melinda Higgins
### Atlanta R Users </br> 06/24/2021

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background-size: 80%
background-image: url(img/ggplot2_masterpiece.png)
background-position: 70% 70%
class: center, top

.footnote[
* Illustrations by Allison Horst, RStudio Artist in Residence, <https://github.com/allisonhorst/stats-illustrations>
]

---

# Be an Artist! 
# Create Awesome Figures with `ggplot2`

---

# Make a Scatterplot

Let's look at the Palmer Penguins dataset again. Make a scatterplot of

```r
library(palmerpenguins)

# Make a scatterplot
ggplot(penguins) + 
  aes(x=bill_length_mm, 
      y=bill_depth_mm, 
      color = species) + 
  geom_point() +
  xlab("Bill Length (mm)") +
  ylab("Bill Depth (mm)") +
  ggtitle("Penguins Bill Dimensions")
```
]

.right-plot[
<img src="MHiggins_IntroToPatchwork.v2_files/figure-html/plot-label-out-1.png" width="100%" />
]

---

# Scatterplot - make plot area

```r
# Step 1 specify dataset 
# penguins for ggplot()
*ggplot(penguins)
```

The basic plot space is created.

]

.right-plot[
<img src="MHiggins_IntroToPatchwork.v2_files/figure-html/plot-label1-out-1.png" width="100%" />
]

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# Scatterplot - add aethetics

```r
# Next add aes (aesthetics)
ggplot(penguins) + 
* aes(x=bill_length_mm,
*     y=bill_depth_mm)
```

Add "aesthetics" using aes - provide the variables for X and Y axes. Notice the `aes()` is added using the `+` operator.

]

.right-plot[
<img src="MHiggins_IntroToPatchwork.v2_files/figure-html/plot-label2-out-1.png" width="100%" />
]

---

# Add a `geom_xxx` - Geometric Object

```r
# Add points to graph
ggplot(penguins) + 
  aes(x=bill_length_mm, 
      y=bill_depth_mm) + 
* geom_point()
```

Add `geom_point()` to add the **points** to the graph.

]

.right-plot[
<img src="MHiggins_IntroToPatchwork.v2_files/figure-html/plot-label3-out-1.png" width="100%" />
]

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# Add Color - use `aes()`

```r
# Add color aesthetic
ggplot(penguins) + 
  aes(x=bill_length_mm, 
      y=bill_depth_mm,
*     color = species) +
  geom_point() 
```

Add `color` option to the aesthetics inside the `aes()`.

]

.right-plot[
<img src="MHiggins_IntroToPatchwork.v2_files/figure-html/plot-label4-out-1.png" width="100%" />
]

---

# Add Labels - to the axes and add a title

```r
# Add axis labels and a title
ggplot(penguins) + 
  aes(x=bill_length_mm, 
      y=bill_depth_mm,
      color = species) + 
  geom_point() +
* xlab("Bill Length(mm)") +
* ylab("Bill Depth (mm)") +
* ggtitle("Penguins Bill Dimensions")
```

Add axis labels with `xlab()` and `ylab()` and add a title with `ggtitle()`.

]

.right-plot[
<img src="MHiggins_IntroToPatchwork.v2_files/figure-html/plot-label5-out-1.png" width="100%" />
]

---

# Great Resources for R Graphics
<hr>

## R Graphics Cookbook

### [https://r-graphics.org/](https://r-graphics.org/)

### [http://www.cookbook-r.com/Graphs/](http://www.cookbook-r.com/Graphs/)

## R-Gallery

### [https://www.r-graph-gallery.com/](https://www.r-graph-gallery.com/)

---

.footnote[See code examples at [http://www.cookbook-r.com/Graphs/Plotting_distributions_(ggplot2)/](http://www.cookbook-r.com/Graphs/Plotting_distributions_(ggplot2)/)]

# Make a histogram with overlaid density curve

```r
# Look at flipper_length_mm
# for Palmer Penguins
# Histogram with density curve
# Use y=..density..
# Overlay with transparent density plot
ggplot(penguins, 
       aes(x=flipper_length_mm)) + 
  geom_histogram(aes(y=..density..),      
                 binwidth=2,
                 colour="black", 
                 fill="white") +
  geom_density(alpha=.2, 
               fill="#FF6666") 
```

]

]

---

# Break out by Facet/Panels

Add `facet_wrap()` to make histogram plots for each penguin species in a different facet or panel.

]

]

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# Pulling it together - make a canvas

# Patchwork!

<img src="img/patchworklogo.png" width="20%" />
.footnote[
Learn more at [https://patchwork.data-imaginist.com/](https://patchwork.data-imaginist.com/) and fun R-Bloggers post [https://www.r-bloggers.com/2020/03/patchwork-r-package-goes-nerd-viral/](https://www.r-bloggers.com/2020/03/patchwork-r-package-goes-nerd-viral/)
]
---

.footnote[
* Illustrations by Allison Horst, RStudio Artist in Residence, <https://github.com/allisonhorst/stats-illustrations>
]
---

## Saving plots as objects

```r
# save a plot as an object
p1 <- ggplot(penguins, 
         aes(x=bill_length_mm, 
             y=bill_depth_mm, 
             color = species)) +
  geom_point()  
  
# plot the object
*p1
```

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![](MHiggins_IntroToPatchwork.v2_files/figure-html/plot-p1obj-out-1.png)

]

---

## Side by Side - use syntax `p1 | p2`

```r
library(ggplot2)
library(patchwork)

# create another plot object
p2 <- ggplot(penguins, 
             aes(x=species, 
                 y=bill_length_mm)) + 
  geom_boxplot() + 
  xlab("Species") +   
  ylab("Bill Depth (mm)")

# arrange the plot objects
*(p1 | p2)
```

]

![](MHiggins_IntroToPatchwork.v2_files/figure-html/plot-side-out-1.png)

]

---

## Stack 2 Plots - use syntax `p2 / p3`

```r
# make another plot
p3 <- 
  ggplot(penguins, 
         aes(x=flipper_length_mm)) + 
  geom_histogram(aes(y=..density..),      
    binwidth=2, colour="black", 
    fill="white") +
  geom_density(alpha=.2, fill="#FF6666") +
  facet_wrap(vars(species))

# arrange plots top / bottom
*p2 / p3
```

]

![](MHiggins_IntroToPatchwork.v2_files/figure-html/plot-stack-out-1.png)

]

---

## Combine - syntax `(p1 | p2)/p3`

```r
# combine syntax
# arrange plots as you like
*(p1 | p2) / p3
```

]

![](MHiggins_IntroToPatchwork.v2_files/figure-html/plot-patch-out-1.png)

]

---

# Thank you!
<hr>

# Melinda Higgins

### Materials for this presentation
[https://melindahiggins2000.github.io/AtlantaRUsers_24June2021/](https://melindahiggins2000.github.io/AtlantaRUsers_24June2021/)

### More about me
[https://melindahiggins.com/](https://melindahiggins.com/)