unix——文件中的列数。

Given a file with data like this (i.e. stores.dat file)

给定一个包含这样数据的文件(即存储)。dat文件)

sid|storeNo|latitude|longitude
2|1|-28.03720000|153.42921670
9|2|-33.85090000|151.03274200

What would be a command to output the number of column names?

输出列名数目的命令是什么?

i.e. In the example above it would be 4. (number of pipe characters + 1 in the first line)

在上面的例子中是4。(第一行中管道字符数+ 1)

I was thinking something like:

我在想:

awk '{ FS = "|" } ; { print NF}' stores.dat

but it returns all lines instead of just the first and for the first line it returns 1 instead of 4

但是它返回所有的行而不是第一行对于第一行它返回1而不是4

10 个解决方案

#1

awk -F'|' '{print NF; exit}' stores.dat

Just quit right after the first line.

就在第一行之后就辞职。

#2

This is a workaround (for me: I don't use awk very often):

这是一个变通方案(对我来说:我不经常使用awk):

Display the first row of the file containing the data, replace all pipes with newlines and then count the lines:

显示包含数据的文件的第一行，用新行替换所有管道，然后数行:

$ head -1 stores.dat | tr '|' '\n' | wc -l

#3

Unless you're using spaces in there, you should be able to use | wc -w on the first line.

除非你在使用空格，否则你应该可以在第一行使用| wc -w。

wc is "Word Count", which simply counts the words in the input file. If you send only one line, it'll tell you the amount of columns.

wc是“单词计数”，它只对输入文件中的单词进行计数。如果只发送一行，它将告诉您列的数量。

#4

You could try

你可以试试

cat FILE | awk '{print NF}'

cat文件| awk '{print NF}'

#5

If you have python installed you could try:

如果你已经安装了python，你可以尝试:

python -c 'import sys;f=open(sys.argv[1]);print len(f.readline().split("|"))' \
    stores.dat

#6

This is usually what I use for counting the number of fields:

这通常是我用来计算字段数的:

head -n 1 file.name | awk -F'|' '{print NF; exit}'

#7

Perl solution similar to Mat's awk solution:

类似于Mat awk解决方案的Perl解决方案:

perl -F'\|' -lane 'print $#F+1; exit' stores.dat

I've tested this on a file with 1000000 columns.

我在一个有1000000列的文件上测试过这个。

If the field separator is whitespace (one or more spaces or tabs) instead of a pipe:

如果字段分隔符是空格(一个或多个空格或制表符)，而不是管道:

perl -lane 'print $#F+1; exit' stores.dat

#8

Based on Cat Kerr response. This command is working on solaris

基于Cat Kerr的反应。这个命令在solaris上工作

awk '{print NF; exit}' stores.dat

#9

you may try:

你可以尝试:

head -1 stores.dat | grep -o \|  | wc -l

#10

select any row in the file (in the example below, it's the 2nd row) and count the number of columns, where the delimiter is a space:

选择文件中的任意一行(在下面的示例中，它是第二行)并计算列的数量，其中分隔符是空格:

sed -n 2p text_file.dat | tr ' ' '\n' | wc -l

#1

awk -F'|' '{print NF; exit}' stores.dat