gdata (version 2.18.0)

update.list: Update the elements of a list

Description

Function to update the elements of a list to contain all of the named elements of a new list, overwriting elements with the same name, and (optionally) copying unnamed elements.

Usage

# S3 method for list
update(object,
       new,
       unnamed=FALSE,
       ...)

Arguments

object

Object to be updated.

new

List or dataframe containing new elements.

unnamed

Logical. If TRUE, unnamed elements of new will be appended to object.

...

optional method arguments (ignored)

Value

A new list constructed from the elements of object by merging the elements of old and new with named items of new replacing the corresponding elements of old. Unnamed elements of new will be appened unless unnamed=FALSE.

See Also

update, merge

Examples

# NOT RUN {
old <- list(a=1,b="red",c=1.37)
new <- list(b="green",c=2.4)

update(old, new)
update.list(old,new)  # equivalent

older <- list(a=0, b="orange", 4, 5, 6)
newer <- list(b="purple", 7, 8, 9)
update(older, newer)               # ignores unnamed elements of newer
update(older, newer, unnamed=TRUE) # appends unnamed elements of newer

# }
# NOT RUN {
<!-- %%data(iris) -->
# }
# NOT RUN {
<!-- %%iris$Species <- as.character(iris$Species) -->
# }
# NOT RUN {
<!-- %%df.old <- cbind(iris[1:5,], letters=1:5) -->
# }
# NOT RUN {
<!-- %%df.new <- df.old[3:5,] -->
# }
# NOT RUN {
<!-- %%df.new$Petal.Width <- df.new$Petal.Width + 0.1 -->
# }
# NOT RUN {
<!-- %% -->
# }
# NOT RUN {
<!-- %%df.old -->
# }
# NOT RUN {
<!-- %%df.new -->
# }
# NOT RUN {
<!-- %%update(df.old, df.new, by=c(letters)) -->
# }