Layer operation sums

operations can be added together to form stacks of operations, which when multiplied by (applied to) layer-like objects, those layer-like objects are distributed over the operations (i.e. copied).

Usage

# S4 method for operation
sum(x, ..., na.rm = FALSE)

# S4 method for operation,operation
+(e1, e2)

# S4 method for operation,numeric
+(e1, e2)

# S4 method for numeric,operation
+(e1, e2)

# S4 method for operation_sum
format(x, ...)

Arguments

x, ...

operations

na.rm

ignored

e1

an operation or numeric()

e2

an operation or numeric()

Value

An operation.

Details

Addition of ggblend operations depends on the types of objects being summed:

• If you add an operation to an operation, they are merged into a single operation that copies input layer-like objects, one for each operation.

• If you add an operation to a numeric() n, it is equivalent to adding * nop()s to that operation.

Examples

library(ggplot2)

# adding operations together creates a sum of operations
adjust(color = "red") + adjust(linewidth = 2)
#> <operation>: (adjust(colour = "red") + adjust(linewidth = 2))

# addition and multiplication obey the distributive law
op = (adjust(aes(y = 11 -x), color = "skyblue") + 1) * (adjust(color = "white", linewidth = 4) + 1)
op
#> <operation>: (adjust(aes(y = ~11 - x), colour = "white", linewidth = 4) + adjust(aes(y = ~11 - x), colour = "skyblue") + adjust(colour = "white", linewidth = 4) + 1)

# multiplication by a geom returns a modified version of that geom,
# distributed over the sum of the operations
data.frame(x = 1:10) |>
  ggplot(aes(x = x, y = x)) +
  geom_line(linewidth = 2) * op