Epi (version 1.1.20)

merge.Lexis: Merge a Lexis object with a data frame

Description

Merge additional variables from a data frame into a Lexis object.

Usage

## S3 method for class 'Lexis':
merge(x, y, id, by, ...)

Arguments

x

an object of class Lexis

y

a data frame

id

the name of the variable in y to use for matching against the variable lex.id in x.

by

if matching is not done by id, a vector of variable names common to both x and y

...

optional arguments to be passed to merge.data.frame

Value

• A Lexis object with additional columns taken from the merged data frame.

Details

A Lexis object can be considered as an augmented data frame in which some variables are time-dependent variables representing follow-up. The Lexis function produces a minimal object containing only these time-dependent variables. Additional variables may be added to a Lexis object using the merge method.

See Also

merge.data.frame, subset.Lexis