linter {MQMF}

linter finds a value in a series using its location in another

Description

linter is a tool for linearly interpolating in a 2-D cartesian space to search out an unknown value between two known points on the x-axis, based on a known value between two known points on the y-axis. This might be answering the question of what would be the length at 50 percent maturity for a curve with no analytical solution. We could find two points in a series of proportion values on the y-axis that bracketed the 50 percent value using the function bracket. They would be associated with the two length values on the x-axis used to generate the predicted proportion values. If we assume the various points in the 2-D space to be approximated by linear relations then the location between the two known x-axis length values corresponding to the L50 would have the same ratio as the 50 percent value has to the two points on the y-axis. See the example for details. The input arguments include five values, left, right, bottom, top, and target. So, left and right are sequential values on the x-axis, bottom and top are the corresponding sequential values on the y-axis, and target is the value we are looking for on the y-axis.

Usage

linter(pars)

Arguments

pars

a vector of 5 values, left, right, bottom, top and target

Value

a single value being the x-axis value between left and right corresponding to the target on the x-axis

See Also

bracket

Examples

 L = seq(60,160,1)
 p=c(a=0.075,b=0.075,c=1.0,alpha=100)
 asym <- srug(p=p,sizeage=L)
 L25 <- linter(bracket(0.25,asym,L)) 
 L50 <- linter(bracket(0.5,asym,L)) 
 L75 <- linter(bracket(0.75,asym,L)) 
 ans <- c(L25,L50,L75,L50-L25,L75-L50)
 {cat("   L25    L50      L75   L50-L25 L75-L50 \n")
 cat(round(ans,4),"\n")}