在 R 编程中压缩数据框的列值 – summarise()函数

R 语言中的summarise()函数用于将数据帧的列的各种值压缩为一个值。

Syntax: summarise(x, expr)

Parameters:
x: Data Frame
expr: Operation to condense data

示例 1：

# R program to condense data
# of a data frame
  
# Loading library 
library(dplyr)
    
# Create a data frame
d <- data.frame( name = c("Abhi", "Bhavesh", "Chaman", "Dimri"),  
                 age = c(7, 5, 9, 16),  
                 ht = c(46, NA, NA, 69), 
                 school = c("yes", "yes", "no", "no") ) 
  
# Calculating min age 
summarise(d, min_age = min(age)) 
    
# Calculating max age 
summarise(d, max_age = max(age)) 

输出：

min_age
1       5
  max_age
1      16

示例 2：

# R program to condense data
# of a data frame
  
# Loading library 
library(dplyr)
    
# Create a data frame
d <- data.frame( name = c("Abhi", "Bhavesh", "Chaman", "Dimri"),  
                 age = c(7, 5, 9, 16),  
                 ht = c(46, NA, NA, 69), 
                 school = c("yes", "yes", "no", "no") ) 
  
# Calculating mean of age 
summarise(d, mean = mean(age)) 
  
# Calculating median of age 
summarise(d, med = median(age)) 

输出：

mean
1 9.25
  med
1   8