dumpObjects {filehash} | R Documentation |
Dump R objects to a filehash database
dumpObjects(..., list = character(0), dbName, envir = parent.frame()) dumpImage(dbName = "Rworkspace") dumpDF(data, dbName = NULL)
... |
R objects to dump |
list |
character vector of names of objects to dump |
dbName |
character, name of database to which objects should be dumped |
envir |
environment from which to obtain objects |
data |
a data frame |
Objects dumped to a database can later be loaded via dbLoad
.
Alternatively, the with
method can be used to evaluate code in
the context of a database. If a database with name dbName
already exists, objects will be inserted into the existing database
(and values for already-existing keys will be overwritten).
dumpDF
is different in that each variable in the data frame is
stored as a separate object in the database. So each variable can be
read from the database separately rather than having to load the
entire data frame into memory.
An object of class "filehash"
is returned.
Roger D. Peng
data <- data.frame(y = rnorm(100), x = rnorm(100), z = rnorm(100)) db <- dumpDF(data, dbName = "dataframe.dump") fit <- with(db, lm(y ~ x + z)) summary(fit)