Linux 计算纯文本文件中字符的出现次数
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/1603566/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Count occurrences of a char in plain text file
提问by cupakob
Is there any way under linux/terminal to count, how many times the char f occurs in a plain text file?
在linux/terminal下有什么办法可以统计一下char f在纯文本文件中出现了多少次？
采纳答案by Cascabel
How about this:
这个怎么样：
fgrep -o f <file> | wc -l
Note: Besides much easier to remember/duplicate and customize, this is about three times (sorry, edit! botched the first test) faster than Vereb's answer.
注意：除了更容易记住/复制和自定义之外，这比 Vereb 的答案快了大约三倍（对不起，编辑！搞砸了第一个测试）。
回答by Vereb
echo $(cat <file> | wc -c) - $(cat <file> | tr -d 'A' | wc -c) | bc
where the A is the character
其中 A 是字符
Time for this command with a file with 4.9 MB and 1100000 occurences of the searched character:
使用具有 4.9 MB 和 1100000 次搜索字符的文件执行此命令的时间：
real 0m0.168s
user 0m0.059s
sys 0m0.115s
回答by Rob Hruska
tr -d '\n' < file | sed 's/A/A\n/g' | wc -l
tr -d '\n' < file | sed 's/A/A\n/g' | wc -l
Replacing the two occurrences of "A" with your character, and "file" with your input file.
用你的角色替换两次出现的“A”，用你的输入文件替换“文件”。
tr -d '\n' < file: removes newlinessed 's/A/A\n/g: adds a newline after every occurrence of "A"wc -l: counts the number of lines
tr -d '\n' < file: 删除换行符sed 's/A/A\n/g: 在每次出现“A”后添加一个换行符wc -l: 计算行数
Example:
例子：
$ cat file
abcdefgabcdefgababababbbba
1234gabca
$ tr -d '\n' < file | sed 's/a/a\n/g' | wc -l
9
回答by Jongo the Gibbon
If all you need to do is count the number of lines containing your character, this will work:
如果您需要做的就是计算包含您的角色的行数，这将起作用：
grep -c 'f' myfile
However, it counts multiple occurrences of 'f' on the same line as a single match.
但是，它会将同一行上多次出现的 'f' 计为一个匹配项。
回答by user1985553
even faster:
甚至更快：
tr -cd f < file | wc -c
Time for this commandwith a file with 4.9 MB and 1100000 occurences of the searched character:
使用具有 4.9 MB 和 1100000 次搜索字符的文件执行此命令的时间：
real 0m0.089s
user 0m0.057s
sys 0m0.027s
Time for Vereb answer with echo, cat, trand bcfor the same file:
时间Vereb答案有echo，cat，tr和bc相同的文件：
real 0m0.168s
user 0m0.059s
sys 0m0.115s
Time for Rob Hruska answer with tr, sedand wcfor the same file:
Rob Hruska 回答tr,sed和wc同一个文件的时间：
real 0m0.465s
user 0m0.411s
sys 0m0.080s
Time for Jefromi answer with fgrepand wcfor the same file:
时间Jefromi答案与fgrep和wc相同的文件：
real 0m0.522s
user 0m0.477s
sys 0m0.023s
