constant.data.frame: Identify variables that are constant within levels of a...

In gmonette/spida15: Collection of miscellaneous functions for mixed models etc. prepared for SPIDA 2009+ (development version)

Usage

constant.data.frame(x, id, all = FALSE, ...)

Arguments

x
id
all
...

Examples

##---- Should be DIRECTLY executable !! ----
##-- ==>  Define data, use random,
##--	or do  help(data=index)  for the standard data sets.

## The function is currently defined as
function (x, id, all = FALSE, ...) 
{
    if (missing(id)) 
        ret <- sapply(x, constant, ...)
    else {
        id <- eval(substitute(id), x, parent.frame())
        if (inherits(id, "formula")) 
            id <- c(model.frame(id, x))
        ret <- sapply(x, function(xx) tapply(xx, id, constant, 
            ...))
        if (all) 
            ret <- apply(ret, 2, all)
    }
    ret
  }

gmonette/spida15 documentation built on May 17, 2019, 7:26 a.m.