GGplot - Scale (Data Transformation)

About

Scales control the mapping between data and aesthetics, and control the display of the matching guide (axis or legend)

Ex: Linear scaling of x and y axes (scales)

See:

• current/scale_continuous.html,
• current/scale_discrete.html,
• current/scale_size.html,
• current/scale_shape.html,
• current/scale_linetype.html (Scale for line patterns)

Articles Related

Definition

Basic

• Change name and range or limits
• All scales take name as first argument
  • axis or legend name
  • can be an expression
• All position scales also take limits argument
• Any data outside of limits is not plotted (but is still used for computation)

Position scales

• Can be used to plot on non-linear scales (scale_x_log10, scale_x_sqrt, …)
• Can also control exactly where breaks occur (with breaks argument) and the amount of extra space on the borders (with the expand argument)

Colour/fill

Colour/fill probably most commonly manipulated

• discrete: hue, brewer, grey, manual
• continuous: gradient, gradient2
• identity

Management

Suppression

Example:

scale_x_continuous(NULL, breaks = NULL) + 
scale_y_continuous(NULL, breaks = NULL)

Documentation

See scale in the doc