Intro to ggplot2

### Example: Point Plot
## Create a chart that shows the relationship between highway mileage and engine displacement

 mpg%>%
      ggplot()+
      geom_point(aes(x=displ, y=hwy))

### Example: Bar Chart
## Create a chart that shows the number of vehicles for each class of vehicle

mpg%>%
  ggplot()+
  geom_bar(aes(x=class))

### Example: Column Chart
## Create a chart that shows the median displacement for each class of vehicle

mpg%>%
  group_by(class)%>%
summarize(mdispl=median(displ))%>%
  ggplot()+
geom_col(aes(x=class, y=mdispl))

### Example: Bot Plot
#create a boxplot that shows the city mileage IQR for different classess of cars

mpg%>%
      ggplot()+
      geom_boxplot(aes(x=class, y=cty))

### Example: Histogram
#Create a histogram showing the highway milage per gallon for the vehicles 

mpg%>%
      ggplot()+
      geom_histogram(aes( x=hwy), binwidth = 1)

###Example: Aesthetics
## Show the relationship between highway mileage and engine displacement. In your chart color code the vehicle by class and vary the size of the points by 

 mpg%>%
      ggplot()+
      geom_point(aes(x=displ, y=cty, color=class, size=factor(year)), alpha=0.5)

###Example: STAT
##Create a chart that shows the median displacement for each vehicle class
mpg%>%
  ggplot()+
geom_pointrange(aes(x=class, y=displ), stat="summary")

###Alternative Example: STAT
##Create a chart that shows the median displacement for each vehicle class
mpg%>%
  ggplot()+
  stat_summary(mapping = aes(x=class, y = displ))

### Example: Position - Dodge 2
##Compare the number of vehicles for the different years

mpg%>%
 ggplot( ) +
  geom_bar(aes(x=class, fill = factor(year)), position = position_dodge2())

### Example: Position - Stack
##Compare the number of vehicles for the different years

mpg%>%
 ggplot( ) +
  geom_bar(aes(x=class, fill = factor(year)), position = position_stack())

### Example: Position - Fill
##Compare the number of vehicles for the different years

mpg%>%
 ggplot( ) +
  geom_bar(aes(x=class, fill = factor(year)), position = position_fill())

### Example: Coord Flip (Boxplot)
#Create a boxplot that shows the city mileage IQR for different classes of cars

mpg%>%
      ggplot()+
      geom_boxplot(aes(x=class, y=cty))+
coord_flip()

### Example: Facet Wrap -Point Plot
## Create a chart that shows the relationship between highway mileage and engine displacement for 1999 and for 2008
mpg%>%
      ggplot()+
      geom_point(aes(x=displ, y=cty))+
  facet_wrap(~year)

### Example: Facet Wrap 2 rows -Point Plot
## Create a chart that shows the relationship between highway mileage and engine displacement for 1999 and for 2008
mpg%>%
      ggplot()+
      geom_point(aes(x=displ, y=cty))+
  facet_wrap(~year, nrow = 2)

###Example, Scale - Point Plot
## Create a chart that shows the relationship between highway mileage and engine displacement for 1999 and for 2008. The scale for your x axis should range from 0-40 in increments of 10 and the scale for your y axis should range from 1.5 to 7 in increments of 0.5

mpg%>%
      ggplot()+
      geom_point(aes(x=displ, y=cty))+
  facet_wrap(~year)+
scale_y_continuous(limits = c(0,40),
                     breaks = seq(0,40, by=10))+
scale_x_continuous(limits = c(1.5,7),
                     breaks = seq(0.5,7, by=1))

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NA

###Example, Theme - Point Plot
## Create a chart that shows the relationship between highway mileage and engine displacement for 1999 and for 2008. The scale for your x axis should range from 0-40 in increments of 10 and the scale for your y axis should range from 1.5 to 7 in increments of 0.5. Use a grey theme.

mpg%>%
      ggplot()+
      geom_point(aes(x=displ, y=cty, color=class), size=3, alpha=0.5)+
  facet_wrap(~year)+
scale_y_continuous(limits = c(0,40),
                     breaks = seq(0,40, by=10))+
scale_x_continuous(limits = c(1.5,7),
                     breaks = seq(0.5,7, by=1))+
  theme_grey()

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###Example, Titles - Point Plot
## Create a chart that shows the relationship between highway mileage and engine displacement for 1999 and for 2008. The scale for your x axis should range from 0-40 in increments of 10 and the scale for your y axis should range from 1.5 to 7 in increments of 0.5. Use a grey theme and label your plot.
mpg%>%
      ggplot()+
      geom_point(aes(x=displ, y=cty, color=class), size=3, alpha=0.5)+
  facet_wrap(~year)+
scale_y_continuous(limits = c(0,40),
                     breaks = seq(0,40, by=10))+
scale_x_continuous(limits = c(1.5,7),
                     breaks = seq(0.5,7, by=1))+
  labs(title = "Relationship Between Highway Mileage & Engine Displacement", y="City Mileage (mpg)", x="Engine Displacement")+
  theme_grey()

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NA

###Example, Adding Layers - Point Plot
## Create a chart that shows the relationship between highway mileage and engine displacement for 1999 and for 2008. The scale for your x axis should range from 0-40 in increments of 10 and the scale for your y axis should range from 1.5 to 7 in increments of 0.5. Use a grey theme and label your plot.Include a trend line
mpg%>%
      ggplot(aes(x=displ, y=cty))+
      geom_point(aes(x=displ, y=cty),size=3, alpha=0.5, color="blue")+
  geom_smooth()+
  facet_wrap(~year)+
scale_y_continuous(limits = c(0,40),
                     breaks = seq(0,40, by=10))+
scale_x_continuous(limits = c(1.5,7),
                     breaks = seq(0.5,7, by=1))+
  labs(title = "Relationship Between Highway Mileage & Engine Displacement", y="City Mileage (mpg)", x="Engine Displacement")+
  theme_grey()