rrx2x: Sieve Test Data Object Plot Coordinates Transformation Functions

Description

Function transform user coordinates of plot to axis coordinates or vise versa.

Usage

rrx2x(x)
rry2y(x)
x2rrx(x)
y2rry(x)

Arguments

Value to transform.

Value

Functions return appropriate transformed value.

Details

The default plot type "rr" uses transformed coordinates, so the user can read percents on y axis and micrometers on x axis, while par('usr') returns coordinates in log(x) and log(log(100/y)). Hence the user can use transformation functions to convert between the types. The "rr" keyword in the name of function, belongs to the log x log-log (usr) space.

Examples

Run this code

# NOT RUN {
data(lignite)
plot(lignite)
# query for exact x coordinates within the plot
if(interactive()) rrx2x(locator()$x)
# query for exact y coordinates within the plot
if(interactive()) rry2y(locator()$y)
# or 
y2rry(36.78794)
# or
rrx2x(par('usr')[1])
# }