| sortedXyData {stats} | R Documentation |
Create a sortedXyData Object
Description
This is a constructor function for the class of sortedXyData
objects. These objects are mostly used in the initial
function for a self-starting nonlinear regression model, which will be
of the selfStart class.
Usage
sortedXyData(x, y, data)
Arguments
x |
a numeric vector or an expression that will evaluate in
|
y |
a numeric vector or an expression that will evaluate in
|
data |
an optional data frame in which to evaluate expressions
for |
Value
A sortedXyData object. This is a data frame with exactly
two numeric columns, named x and y. The rows are
sorted so the x column is in increasing order. Duplicate
x values are eliminated by averaging the corresponding y
values.
Author(s)
José Pinheiro and Douglas Bates
See Also
selfStart, NLSstClosestX,
NLSstLfAsymptote, NLSstRtAsymptote
Examples
DNase.2 <- DNase[ DNase$Run == "2", ]
sortedXyData( expression(log(conc)), expression(density), DNase.2 )