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Functions

Compute the numeric sum of a file

Terminal - Compute the numeric sum of a file
sed i"+" file.txt | xargs echo 0 |bc
2011-02-09 10:14:22
User: rubenmoran
Functions: echo sed xargs
1
Compute the numeric sum of a file

In the file data.txt there is a single column of numbers. Sed adds a "+" between lines and xargs prepares the output for bc. The "echo 0" is to avoid to have a "+" at the beginning of the line.

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

What others think

Hmm... interesting, but we can do better.

First let's get rid of xargs:

echo 0 $(sed i+ file.txt) | bc

Next, use the right tools for the job:

paste -sd+ < file.txt | bc

paste (join together) -s (serial, in one line) -d+ (delimited with +)

Comment by flatcap 187 weeks and 4 days ago

Thanks flatcap! Those are much better, xargs even fails for big files.

Huge difference, the second one is the best:

ruben@studio:~$ seq 1000000 > file.txt

ruben@studio:~$ time echo 0 $(sed i+ file.txt) | bc

500000500000

real 0m5.064s

user 0m5.150s

sys 0m0.260s

ruben@studio:~$ time paste -sd+ < file.txt | bc

500000500000

real 0m0.851s

user 0m0.820s

sys 0m0.040s

Cooool....

Cheers.

Comment by rubenmoran 187 weeks and 4 days ago
Comment by jp 186 weeks and 2 days ago

So many ways to do it.

The one with paste -s is the best.

Here's another rather silly one:

sed i"+" file.txt | tr '\n' ' ' | sed 's/^/0 /' | sed 's/$/\n/' | bc

Comment by jp 186 weeks and 2 days ago

Your point of view

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