在 R 编程中计算向量的连续元素对之间的差异 - diff()函数

R 语言中的diff()函数用于查找向量的每对连续元素之间的差异。

Syntax: diff(x, lag, differences)

Parameters:
x: vector or matrix
lag: period between elements
differences: Order of difference

示例 1：

# R program to find the difference
# between each pair of elements of a vector
  
# Creating a vector
x1 <- c(8, 2, 5, 4, 9, 6, 54, 18)
x2 <- c(1:10)
x3 <- c(-1:-8)
  
# Calling diff() function
diff(x1)
diff(x2)
diff(x3)

输出：

[1]  -6   3  -1   5  -3  48 -36
[1] 1 1 1 1 1 1 1 1 1
[1] -1 -1 -1 -1 -1 -1 -1

示例 2：

# R program to find the difference
# between each pair of elements of a vector
  
# Creating a vector
x1 <- c(8, 2, 5, 4, 9, 6, 54, 18)
x2 <- c(1:10)
  
# Calling diff() function
diff(x1, lag = 2, differences = 1)
diff(x2, lag = 1, differences = 2)

输出：

[1] -3  2  4  2 45 12
[1] 0 0 0 0 0 0 0 0

在这里，在上面的代码中，'lag' 告诉值之间的周期，即lag = 2表示，计算第 1 和第 3 个值、第 2 和第 4 个值等之间的差异，而 'differences' 告诉diff()函数被调用，即差异 = 2意味着diff()函数在向量上被调用两次。