creating a sequence of numbers, one per line in a file

Question

Is there a way to create out of thin air, a file that is a sequence of numbers, starting at a given number, one per line?

something like

magic_command start 100 lines 5 > b.txt

and then, b.txt would be

100
101
102
103
104

Solution 1

There is already a command for this:

seq 100 104

will print these numbers on separate lines:

100
101
102
103
104

So just direct this output into a file:

seq 100 104 > my_file.txt

and seq 100 2 104 will print in increments of two, namely: 100, 102, 104

Solution 2

Linux ships with the seq command which does exactly that. If you don't have the seq command, it's an easy one-liner:

i=100; while [ $i -le 104 ]; do echo $i; i=$((i+1)); done >b.txt

or in ksh/bash/zsh

for ((i=100; i<=104; i++)); do echo $i; done >b.txt

or in zsh

print -l {100..104} >b.txt

Solution 3

bash:

printf '%s\n' {100..105}

perl:

perl -le 'print for 100..104'

bc:

echo 'for (i = 100 ; i <= 104 ; ++i) i' | bc

dc:

echo '100 104 sb [p 1 + d lb !<m] sm lm x' | dc

Solution 4

If you don't mind a space in front of most of them:

echo -e {100..104}\\n >numbers-file.txt

Without the space but with an extra command:

echo {100..104} | sed 's/ /\n/g' >numbers-file.txt

---

Edit for a bonus vim command (open vim):

i100[esc]qqyyp[ctrl-a]q2@q:w numbers-file.txt

For more numbers, increase 2 accordingly.

Solution 5

Besides using seq, while, for, printf, perl, echo as shown in previous example, you can also use Python

python -c "print list(range(100,105))"

Example:

[user@linux ~]~ python -c "print list(range(100,105))"
[100, 101, 102, 103, 104]
[user@linux ~]~ 

View more solutions

Comments

[Matthew]

no need to call it .txt

[Duck]

wooooooooooooooooooooooooooooooooooooooowwwwwwwwwww, you are a genius. That's it. I love unix more every second! Thanks.

[Duck]

is there a place where I can learn about little gems like seq? I am interested in commands that can create stuff out of thin air, like sequence of numbers, files that contain the same text line x times, commands that can generate sequence of letters "a, b, c, d..", stuff like that. thanks

[Christian Mann]

I love zsh more and more every day.

[Cascabel]

@DigitalRobot: At some point you're probably going to find yourself just writing perl one-liners.

[jamesbtate]

@Gilles your first example will continue forever because you never increment $i.

[camh]

You can use printf(1) to not get the space at the start of the line: printf '%s\n' {100..104}

[Matthew]

+1 never seen anyone use bc or dc like that before

[Matthew]

and it strikes me that your dc answer is uncommonly wry and upvote-worthy

[Peter John Acklam]

It was unnecessarily complicated, but not on purpose, so I have simplified it now.

[Kaz]

@SpaceDog Your love is misplaced. seq is from GNU Coreutils, not Unix. GNU even stands for GNU is Not Unix!

[don_crissti]

creating a sequence of numbers, one per line... and btw, this only works with python2.