EXPR the value of 2 files

[markbusu]

Hi guys,

Having some trouble finding a method to perform a calculation between the contents of two files... For example

Say i have:

File 1

-------------
1
23
54343
123
45676
8855
-------------

File 2

-------------
9087
576
7897
4778
665
4545
-------------

I would like to add or divide the contents of the two files between each other, such as:

1*9087
23*576
54343*7897
123*4778
45676*665
8855*4545

and finally output the result to another file...

How am I able to add the contents of these files?

Note: The number of lines between each file is always the same...

Thanks for any help you can offer!!

Mark

[radoulov]

With zsh:

printf "%d\n" $(paste -d\* file1 file2)>final

This should work with other shells:

printf "%s\n" $(paste -d\* file1 file2)|bc>final

Or just use awk:

awk 'NR==FNR{_[FNR]=$0;next}$0=$0*_[FNR]' file1 file2>final

Or:

eval printf "%s\\\n" $(printf '$((%s)) ' $(paste -d\* file1 file2))

P.S. Post modified ...

[wje_lf]

I like the second alternative:

printf "%s\n" $(paste -d\* file1 file2)|bc>final

but it can be cleaned up thus:

paste -d\* file1 file2 | bc -q > final

[radoulov]

Absolutely right
I didn't realize that I was in zsh when I posted this:

printf "%d\n" $(paste -d\* file1 file2)

And after that I tried to give more portable solution in a hurry

[markbusu]

Thanks for the tips guys!!

I tried using the cleaned version, however i dont get any output back...

Im using Bash... and i get the following output:

# ./sed.sh
$ paste -d\* c.txt d.txt | bc -q > final
+ paste '-d*' c.txt d.txt
+ bc -q

Do you know what might be the cause of this?

Thanks!

[radoulov]

What's the output of:

cat final

[markbusu]

Perfect! worked like a charm...

Thanks m8!

[markbusu]

Hi again

So i needed to make a change, rather then a multiplication, i would need to perform a division... such as:

paste -d\/ file1 file2 | bc -q > final

However, the problem that the file final only uses whole numbers... however im performing a division on ms... such as 0.0000445..

Is there any way of getting a number to 10 decimal points?

Thanks!

[radoulov]

bc<<! >final
scale=10
$(paste -d\/ file1 file2)
!

If you want a leading 0:

printf "%.10f\n" $(paste -d\/ file1 file2|bc -l)>final

[markbusu]

Thanks once again... that did the trick...

Ok im nearly ready here... however encountered another issue...

Basically im parsing a document which contains SQL Statements that were run... calculating the number of times a SQL Statement was run agianst the total execution time...

However, when i encounter an issue were the SQL Statement times run is 0 and the total execution time is 0... i.e 0 / 0 generats the following error:

Runtime error (func=(main), adr=11): Divide by zero.

The error is generated by bc. Is there a method of handling this exception, therefore should the division be 0/0... You return the result 0?

Thanks once agani guys!