plfit.nls2 - Plot an nls2 Object for Studying the Fitted Values


On to:
DESCRIPTION
USAGE
REQUIRED-ARGUMENTS
OPTIONAL-ARGUMENTS
CONSTRAINTS
DETAILS
SEE-ALSO
EXAMPLE



DESCRIPTION:

Plot:
- the observed values against the fitted values,
- the observed and fitted values against the independent variables. The fitted values are joined by a solid line. In case of several curves, the fitted values of each curve are joined by lines of different types.


USAGE:
plfit.nls2(nls2.object, 
           step=nls2.object$nb.steps, 
           wanted=list(O.F=T, X.OF=T), 
           n.fitted=0,
           smooth=F, labels=NULL, title="", figs=c(2, 2), 
           ask.pause=T, ask.modify=F,....)

Sommaire

REQUIRED ARGUMENTS:

nls2.object
an object of class `nls2'.

OPTIONAL ARGUMENTS:
step
when the `nls2.object' has been created by an alternated method of estimation, the index of the step requested. By default, the last step.
wanted
a list that specifies the graphs requested; Its components are logics that should be TRUE if the corresponding graphs are requested.
"wanted" components and their meanings are:
O.F: the fitted values are plotted against the observed values.
X.OF: the observed and fitted values are plotted against the independent variable. Available only when there is a single independent variable.
n.fitted
the number of regularly spaced points on the x-axis where the regression function is calculated for improving the fitted curves.
If equal to 0, only the fitted values stored in `nls2.object' are taken into account.
smooth
a logic that should be TRUE if the points of the observed values are to be joined. If so, they are joined by a dotted line after smoothing.
labels,title,figs,ask.pause,ask.modify,...
See `pldnls2'.

Sommaire


CONSTRAINTS:

- A graphical device should have been previously activated.

- The data frame containing the observations must be available, either saved in the `nls2.object', or through the name that appears in the `nls2.object', component `call'. It is then assumed that this data frame has been neither deleted nor modified since the `nls2.object' was created.

- When the argument `n.fitted' is positive, function `loadnls2' should have been previously called.


DETAILS:

This function is a method for the generic function `plfit' for class `nls2'. It can be invoked by calling `plfit' for an object of the appropriate class, or directly by calling `plfit.nls2' regardless of the class of the object.


SEE ALSO:

Sommaire




EXAMPLE:

   X11()
   plfit(nls2.out)

Sommaire


- Mon Sep 30 1996 -