## AWK equation evaluation.

AWK equation evaluation.
# 1
11-22-2007
AWK equation evaluation.

Hi,

Is there a way to evaluate an equation contained in a string within an AWK script?

For example:
A = "(5*2)-1" (this equation is read from a file and varies line by line)

In this example, I can't see any way to get an answer of 9 unless I do:

cmd = "awk 'BEGIN{print "A"}'"
cmd | getline A

The above method works fine but it's rather slow when dealing with large files!

Does anybody know of a better way of achieving the same result within the main AWK script?

Steve
 srdgeo View Public Profile for srdgeo Find all posts by srdgeo
# 2
11-22-2007
Hi.

Many interpreted languages have an eval feature, e.g. snobol, perl,.

I don't know of one for awk, but I'd be happy to learn of one ... cheers, drl
 drl View Public Profile for drl Find all posts by drl
# 3
11-22-2007
something educational to read up on....
 vgersh99 View Public Profile for vgersh99 Find all posts by vgersh99
# 4
11-23-2007
Quote:
Originally Posted by vgersh99
something educational to read up on....

Thanks for your help! The modified calc3 code does exactly what I want and is 15 times faster than the method I was using!
 srdgeo View Public Profile for srdgeo Find all posts by srdgeo

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