tidytable (version 0.5.1)

slice.: Choose rows by position

Description

Choose rows by their ordinal position in a data.table. Grouped data.tables use the ordinal position within the group.

Usage

slice.(.df, rows = 1:5, by = NULL)
slice_head.(.df, n = 5, by = NULL)
slice_tail.(.df, n = 5, by = NULL)
slice_max.(.df, order_by, n = 1, by = NULL)
slice_min.(.df, order_by, n = 1, by = NULL)
dt_slice(.df, rows = 1:5, by = NULL)
dt_slice_head(.df, n = 5, by = NULL)
dt_slice_tail(.df, n = 5, by = NULL)
dt_slice_min(.df, order_by, n = 1, by = NULL)
dt_slice_max(.df, order_by, n = 1, by = NULL)

Arguments

.df

A data.frame or data.table

rows

Integer row values. Provide either positive values to keep, or negative values to drop. The values provided must be either all positive or all negative.

by

Columns to group by

n

Number of rows to grab

order_by

Variable to arrange by

Examples

# NOT RUN {
test_df <- data.table(
  x = c(1,2,3,4),
  y = c(4,5,6,7),
  z = c("a","a","a","b"))

test_df %>%
  slice.(1:4)

test_df %>%
  slice.(1, by = z)

test_df %>%
  slice_head.(1, by = z)

test_df %>%
  slice_tail.(1, by = z)

test_df %>%
  slice_max.(order_by = x, by = z)

test_df %>%
  slice_min.(order_by = y, by = z)
# }