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Summarise columns of a data frame

summarise.Rd

Summarise creates a new data frame that will have one row per group.

Usage

summarise(.data, ..., .frame = NULL, .env = parent.frame())

# S3 method for class 'data.frame'
summarise(.data, ..., .frame = NULL, .env = parent.frame())

# S3 method for class 'group_df'
summarise(.data, ..., .frame = NULL, .env = parent.frame())

# S3 method for class 'nest_df'
summarise(.data, ..., .frame = NULL, .env = parent.frame())

summarise_(data, x, frame = NULL, env = parent.frame())

# S3 method for class 'data.frame'
summarise_(data, x, frame = NULL, env = parent.frame())

# S3 method for class 'group_df'
summarise_(data, x, frame = NULL, env = parent.frame())

# S3 method for class 'nest_df'
summarise_(data, x, frame = NULL, env = parent.frame())

Arguments

.data, data

A data frame.

...

Expressions to be evaluated.

.frame, frame

A character vector of column names referred to in x. This subsets the data frame to only specified columns before evaluation. This provides safer evaluation by preventing accidental use of spurious global variables in place of column names or accidental use of spurious column names in place of global variables.

.env, env

An environment to look for objects outside those in data.

x

A character vector with name-value pairs of expressions.

Value

data.frame

See also

dplyr::summarise()

Examples

#----------------------------------------------------------------------------
# summarise() examples
#----------------------------------------------------------------------------
library(bkdat)

df <- data.frame(a = c(1, 2, 3), b = c(4, 5, 6))
summarise(df, mean = mean(a), median = median(b))
#>   mean median
#> 1    2      5
summarise_(df, c(mean = "mean(a)", median = "median(b)"))
#>   mean median
#> 1    2      5