如何按百分比分割文件.线？
假设我想将文件分成3个部分(60％/ 20％/ 20％部分),我可以手动执行此操作,-_-：
- $wc -l brown.txt
- 57339 brown.txt
- $bc <<< "57339 / 10 * 6"
- 34398
- $bc <<< "57339 / 10 * 2"
- 11466
- $bc <<< "34398 + 11466"
- 45864
- bc <<< "34398 + 11466 + 11475"
- 57339
- $head -n 34398 brown.txt > part1.txt
- $sed -n 34399,45864p brown.txt > part2.txt
- $sed -n 45865,57339p brown.txt > part3.txt
- $wc -l part*.txt
- 34398 part1.txt
- 11466 part2.txt
- 11475 part3.txt
- 57339 total
但我相信有更好的方法！
有一个实用程序将行号作为参数,这些行号应成为每个相应新文件的第一个：csplit.这是它的
POSIX version的包装：
- #!/bin/bash
- usage () {
- printf '%s\n' "${0##*/} [-ks] [-f prefix] [-n number] file arg1..." >&2
- }
- # Collect csplit options
- while getopts "ksf:n:" opt; do
- case "$opt" in
- k|s) args+=(-"$opt") ;; # k: no remove on error,s: silent
- f|n) args+=(-"$opt" "$OPTARG") ;; # f: filename prefix,n: digits in number
- *) usage; exit 1 ;;
- esac
- done
- shift $(( OPTIND - 1 ))
- fname=$1
- shift
- ratios=("$@")
- len=$(wc -l < "$fname")
- # Sum of ratios and array of cumulative ratios
- for ratio in "${ratios[@]}"; do
- (( total += ratio ))
- cumsums+=("$total")
- done
- # Don't need the last element
- unset cumsums[-1]
- # Array of numbers of first line in each split file
- for sum in "${cumsums[@]}"; do
- linenums+=( $(( sum * len / total + 1 )) )
- done
- csplit "${args[@]}" "$fname" "${linenums[@]}"
在要拆分的文件的名称之后,它采用拆分文件的大小相对于它们的总和的比率,即,
- percsplit brown.txt 60 20 20
- percsplit brown.txt 6 2 2
- percsplit brown.txt 3 1 1
都是等价的.
与问题案例类似的用法如下：
- $percsplit -s -f part -n 1 brown.txt 60 20 20
- $wc -l part*
- 34403 part0
- 11468 part1
- 11468 part2
- 57339 total
但编号从零开始,并且没有txt扩展名. GNU version支持–suffix格式选项,该选项允许.txt扩展,并且可以添加到接受的参数中,但这需要比getopts更精细的解析它们.
