Sequence Generation:
生成规律的序列。seq是一个带有默认方法的标准通用。seq.int是一种原始的东西,它可以快得多,但也有一些限制。seq_along和seq_len是两个常见情况的参数。
使用方法:
参数说明:
from :生成向量的起点。
to :生成向量的终点。
by :序列的增量,默认步长为1(可修改)。
length.out :这个序列的输出长度。
对于seq和seq.int来说,如果分数的话,将会被四舍五入。
参考1: R语言中seq函数的用法
参考2:
在一个文档中定位到第一个空行,读取其后的所有文本 get.msg <- function(path) { con <- file(path, open = "rt", encoding = "latin1") text <- readLines(con) # The message always begins after the first full line break msg <-... 文档定位第空行读取其所文本
get.msg <- function(path)
{
con <- file(path, open = "rt", encoding = "latin1")
text <- readLines(con)
# The message always begins after the first full line break
msg <- text[seq(which(text == "")[1]+1, length(text), 1)]
close(con)
return(paste(msg, collapse = "\n"))
}
报错:
Error in seq.default(which(text == "")[1]+1, length(text), 1) :
'from' cannot be NA, NaN or infinite 展开 示例文档:
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
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