R plotting

R has powerful builtin plotting capabilities

This cheatsheet uses ggplot2. For more info on the R-built-in graphics-package see: rdocumentation.org

dot & line charts

Using dataframes:

library(ggplot2)
my_plot = ggplot(myDataframe, aes(x = col1, y = col2)) + geom_point()
print(my_plot)

The logic behind: You define the aesthetics (aes) and then add (+) a layer with points (geom_points)

Using vectors:

ggplot(data = NULL, aes(x = c(1,2,3,4,5), y = c(25,16,9,4,1))) + geom_point()

Styles of plot
points	... + geom_point()
line	... + geom_line()
color	aes(x = ..., y = ..., color = cat_col)... different colors for different categories

Axis
log scale on x	... + scale_x_log10()
log scale on y	... + scale_y_log10()
include 0	... + expand_limits(y = 0)

Column charts

plot the values as columns:

ggplot(df, aes(x = factor(cat_col), y = value_col)) + geom_col()

plot the counts as columns:

ggplot(df, aes(x = factor(value_col))) + geom_bar()

Histogram

Plot distribution of values:

ggplot(df, aes(x = value_col)) + geom_histogram(binwidth=3)

Box Plot

Compare different distributions:

ggplot(df, aes(x = cat_col, y = value_col)) +  geom_boxplot()

Plot functions

To smoothly plot a curved function:

my_func <- function(x) sqrt(x) # - x**2
x_val_df = data.frame(x_val = c(0, 10))
ggplot(x_val_df, aes(x = x_val)) + stat_function(fun = my_func, geom = "line")

More info in this e-book: r-graphics.org/