R语言seq()函数的调用方法

看到有很多读者浏览了这篇文章，心里很是开心，为了能够更好地帮助大家，决定再修改一下，帮助大家更好地理解。

--------修改于：2018年4月28日

为了方便大家在开发环境中直接实验测试代码，下面，我将说明和函数的用法全部用英文给出（避免乱码），并加以注释，希望能够对大家有所帮助！

首先，我们来看一个seq()函数应用的实例！

x <- seq(0, 10, by = 0.01)
y <- sin(x)
plot(y)

下面，我们来看函数的主要使用方法！

注意：在本文调用函数时，均采用写出入口参数名的方法，比如：

seq(from = 1, to = 2)

这样函数的调用更加清晰，在调用较多函数时，不会发生混乱和参数匹配错误。

方式一：seq(from, to)

from：生成向量的起点，to：生成向量的终点，默认步长为1（可修改）

a <- seq(from = 1, to = 2)
# [1, 2]

方式二：seq(from, to, by = )

by：向量元素之间的步长

a <- seq(from = 1, to = 3, by = 0.5)
# [1, 1.5, 2, 2.5, 3]

方式三：seq(from, to, length.out = )

length.out：向量中元素数目

a <- seq(from = 1, to = 3, length.out = 5)
# [1, 1.5, 2, 2.5, 3]

方式四：seq(along.with = )

along.with：表示生成的向量为现有一向量元素的索引

x <- c(1.2, 5.2, 6.3, 4.6)
a <- seq(along.with = x)
# [1, 2, 3, 4]

方式五：seq(from)

该方式和方式四功能相似

x <- c(1.2, 5.2, 6.3, 4.6)
a <- seq(from = x)
# [1, 2, 3, 4]

方式6：seq(length.out = )

生成从1开始，步长为1，长度为length.out的向量

a <- seq(length.out = 5)
# [1, 2, 3, 4, 5]

上述几种方式为较为常见的方式，详细的函数说明如下：

Sequence Generation

Description

Generate regular sequences. seq is a standard generic with a default method. seq.int is a primitive which can be much faster but has a few restrictions. seq_along and seq_len are very fast primitives for two common cases.

---------------------------------------------

Usage

seq(...)
## Default S3 method:
seq(from = 1, to = 1, by = ((to - from)/(length.out - 1)),
length.out = NULL, along.with = NULL, ...)
seq.int(from, to, by, length.out, along.with, ...)
seq_along(along.with)

seq_len(length.out)

---------------------------------------------

Arguments

1：...

arguments passed to or from methods.

2：from, to

the starting and (maximal) end values of the sequence. Of length 1 unless just from is supplied as an unnamed argument.

3：by

number: increment of the sequence.

4：length.out

desired length of the sequence. A non-negative number, which for seq and seq.int will be rounded up if fractional.

5：along.with

take the length from the length of this argument.

参考：https://blog.csdn.net/jiluben/article/details/40024607

到此这篇关于R语言seq()函数的调用方法的文章就介绍到这了,更多相关R语言seq()函数内容请搜索脚本之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持脚本之家！

最新评论