session3: end of session3

session_3/slides.Rmd

@@ -3,6 +3,8 @@ title: "R#3: stats with ggplot2"
 author: "Laurent Modolo [laurent.modolo@ens-lyon.fr](mailto:laurent.modolo@ens-lyon.fr)"
 date: "08 Nov 2019"
 output:
+  slidy_presentation:
+    highlight: tango
   beamer_presentation:
     theme: metropolis
     slide_level: 3
@@ -10,8 +12,6 @@ output:
     df_print: tibble
     highlight: tango
     latex_engine: xelatex
-  slidy_presentation:
-    highlight: tango
 ---
 
 ```{r setup, include=FALSE, cache=TRUE}
@@ -23,6 +23,7 @@ library(tidyverse)
 The goal of this practical is to practices advanced features of `ggplot2`.
 
 The objectives of this session will be to:
+
 - learn about statistical transformations
 - practices position adjustments
 - change the coordinate systems
@@ -95,4 +96,175 @@ You can colour a bar chart using either the `colour` aesthetic, or, more usefull
 ```{r diamonds_barplot_fill, cache = TRUE, fig.width=8, fig.height=4.5, message=FALSE}
 ggplot(data = diamonds) + 
   geom_bar(mapping = aes(x = cut, fill = cut))
-```
\ No newline at end of file
+```
+
+## Position adjustments
+
+You can also use `fill` with another variable:
+
+```{r diamonds_barplot_fill_clarity, cache = TRUE, fig.width=8, fig.height=4.5, message=FALSE}
+ggplot(data = diamonds) + 
+  geom_bar(mapping = aes(x = cut, fill = clarity))
+```
+
+## Position adjustments
+
+The stacking is performed by the position adjustment `position`
+
+```{r diamonds_barplot_pos_identity, cache = TRUE, fig.width=8, fig.height=4.5, message=FALSE}
+ggplot(data = diamonds,
+       mapping = aes(x = cut, colour = clarity)) + 
+  geom_bar(fill = NA, position = "identity")
+```
+
+## Position adjustments
+
+The stacking is performed by the position adjustment `position`
+
+```{r diamonds_barplot_pos_fill, cache = TRUE, fig.width=8, fig.height=4.5, message=FALSE}
+ggplot(data = diamonds) + 
+  geom_bar(mapping = aes(x = cut, fill = clarity),
+           position = "fill")
+```
+
+## Position adjustments
+
+The stacking is performed by the position adjustment `position`
+
+```{r diamonds_barplot_pos_dodge, cache = TRUE, fig.width=8, fig.height=4.5, message=FALSE}
+ggplot(data = diamonds) + 
+  geom_bar(mapping = aes(x = cut, fill = clarity),
+           position = "dodge")
+```
+
+## Position adjustments
+
+The stacking is performed by the position adjustment `position`
+
+```{r mpg_point_pos_jitter, cache = TRUE, fig.width=8, fig.height=4.5, message=FALSE}
+ggplot(data = mpg) + 
+  geom_point(mapping = aes(x = displ, y = hwy),
+             position = "jitter")
+```
+
+## Position adjustments
+
+The stacking is performed by the position adjustment `position`
+
+```{r mpg_jitter, cache = TRUE, fig.width=8, fig.height=4.5, message=FALSE}
+ggplot(data = mpg) + 
+  geom_jitter(mapping = aes(x = displ, y = hwy))
+```
+
+## Position adjustments challenges
+
+- What is the problem with this plot? How could you improve it?
+```{r mpg_point, eval=F, message=FALSE}
+ggplot(data = mpg, mapping = aes(x = cty, y = hwy)) + 
+  geom_point()
+```
+- What parameters to `geom_jitter()` control the amount of jittering?
+- Compare and contrast `geom_jitter()` with `geom_count()`
+- What’s the default position adjustment for `geom_boxplot()` ? Create a visualisation of the `mpg` dataset that demonstrates it.
+
+## Coordinate systems
+
+Cartesian coordinate system where the x and y positions act independently to determine the location of each point. There are a number of other coordinate systems that are occasionally helpful.
+
+## Coordinate systems
+
+```{r mpg_boxplot, cache = TRUE, fig.width=8, fig.height=4.5, message=FALSE}
+ggplot(data = mpg, mapping = aes(x = class, y = hwy)) + 
+  geom_boxplot()
+```
+
+## Coordinate systems
+
+```{r mpg_boxplot_flip, cache = TRUE, fig.width=8, fig.height=4.5, message=FALSE}
+ggplot(data = mpg, mapping = aes(x = class, y = hwy)) + 
+  geom_boxplot() +
+  coord_flip()
+```
+
+## Coordinate systems
+
+```{r diamonds_bar, cache = TRUE, fig.width=8, fig.height=4.5, message=FALSE}
+bar <- ggplot(data = diamonds) + 
+  geom_bar(
+    mapping = aes(x = cut, fill = cut), 
+    show.legend = FALSE,
+    width = 1
+  ) + 
+  theme(aspect.ratio = 1) +
+  labs(x = NULL, y = NULL)
+```
+**3_d**
+
+## Coordinate systems
+
+```{r diamonds_bar_plot, echo=F, cache = TRUE, fig.width=8, fig.height=4.5, message=FALSE}
+bar
+```
+
+**3_d**
+
+## Coordinate systems
+```{r diamonds_bar_flip, cache = TRUE, fig.width=8, fig.height=4.5, message=FALSE}
+bar + coord_flip()
+```
+
+## Coordinate systems
+
+```{r mpg_jitter_noquickmap, cache = TRUE, fig.width=8, fig.height=4.5, message=FALSE}
+ggplot(data = mpg) + 
+  geom_jitter(mapping = aes(x = cty, y = hwy))
+```
+
+## Coordinate systems
+
+```{r mpg_jitter_quickmap, cache = TRUE, fig.width=4.5, fig.height=3.5, message=FALSE}
+ggplot(data = mpg) + 
+  geom_jitter(mapping = aes(x = cty, y = hwy)) +
+  coord_quickmap()
+```
+
+## Coordinate systems
+```{r diamonds_bar_polar, cache = TRUE, fig.width=8, fig.height=4.5, message=FALSE}
+bar + coord_polar()
+```
+
+## Coordinate systems challenges
+
+- Turn a stacked bar chart into a pie chart using `coord_polar()`.
+- What does `labs()` do? Read the documentation.
+- What does the plot below tell you about the relationship between `city` and highway `mpg`? Why is `coord_fixed()` important? What does `geom_abline()` do?
+
+```{r mpg_point_fixed, eval = F, cache = TRUE, fig.width=4.5, fig.height=3.5, message=FALSE}
+ggplot(data = mpg, mapping = aes(x = cty, y = hwy)) +
+  geom_point() + 
+  geom_abline() +
+  coord_fixed()
+```
+
+## Coordinate systems challenges
+
+```{r diamonds_barplot_pos_fill_polar, cache = TRUE, fig.width=8, fig.height=4.5, message=FALSE}
+ggplot(data = diamonds) + 
+  geom_bar(mapping = aes(x = cut, fill = clarity),
+           position = "fill") +
+  coord_polar()
+```
+
+## Coordinate systems challenges
+
+```{r mpg_point_nofixed_plot, eval = T, cache = TRUE, fig.width=8, fig.height=3.5, message=FALSE}
+ggplot(data = mpg, mapping = aes(x = cty, y = hwy)) +
+  geom_point() +  geom_abline()
+```
+
+## Coordinate systems challenges
+
+```{r mpg_point_fixed_plot, eval = T, cache = TRUE, fig.width=8, fig.height=3.5, message=FALSE}
+ggplot(data = mpg, mapping = aes(x = cty, y = hwy)) +
+  geom_point() +  geom_abline() + coord_fixed()
+```

web/3_d

+bar <- ggplot(data = diamonds) + 
+  geom_bar(
+    mapping = aes(x = cut, fill = cut), 
+    show.legend = FALSE,
+    width = 1
+  ) + 
+  theme(aspect.ratio = 1) +
+  labs(x = NULL, y = NULL)
\ No newline at end of file