slice: Select rows by position.

In sctyner/dplyr050: A Grammar of Data Manipulation

Description

Slice does not work with relational databases because they have no intrinsic notion of row order. If you want to perform the equivalent operation, use filter() and row_number().

Usage

slice(.data, ...)

slice_(.data, ..., .dots)

Arguments

.data	A tbl. All main verbs are S3 generics and provide methods for tbl_df, tbl_dt and tbl_sql.
...	Integer row values
.dots	Used to work around non-standard evaluation. See vignette("nse") for details.

See Also

Other single.table.verbs: arrange, filter, mutate, select, summarise

Examples

slice(mtcars, 1L)
slice(mtcars, n())
slice(mtcars, 5:n())

by_cyl <- group_by(mtcars, cyl)
slice(by_cyl, 1:2)

# Equivalent code using filter that will also work with databases,
# but won't be as fast for in-memory data. For many databases, you'll
# need to supply an explicit variable to use to compute the row number.
filter(mtcars, row_number() == 1L)
filter(mtcars, row_number() == n())
filter(mtcars, between(row_number(), 5, n()))

sctyner/dplyr050 documentation built on May 17, 2019, 2:22 p.m.