tidyfst (version 1.0.0)

top_dt: Select top (or bottom) n rows (by value)

Description

Get the top entries (rows) according to the values of specified columns. One can get the top or bottom ones according to number or proportion.

In top_dt, you can use an API for both functionalities in `top_n_dt()` and `top_frac_dt()`.

Usage

top_dt(.data, wt = NULL, n = NULL, prop = NULL)
top_n_dt(.data, n, wt = NULL)
top_frac_dt(.data, prop, wt = NULL)

Arguments

.data

data.frame

wt

(Optional). The variable to use for ordering. If not specified, defaults to the last variable in the data.frame.

n

Number of rows to return. Will include more rows if there are ties. If n is positive, selects the top rows. If negative, select the bottom rows.

prop

Fraction of rows to return. Will include more rows if there are ties. If prop is positive, selects the top rows. If negative, select the bottom rows.

Value

data.table

See Also

top_n

Examples

# NOT RUN {
iris %>% top_n_dt(10,Sepal.Length)
iris %>% top_n_dt(-10,Sepal.Length)
iris %>% top_frac_dt(.1,Sepal.Length)
iris %>% top_frac_dt(-.1,Sepal.Length)

# For `top_dt`, you can use both modes above
iris %>% top_dt(Sepal.Length,n = 10)
iris %>% top_dt(Sepal.Length,prop = .1)
# }