Make awk gsub take value of for loop


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# 15  
This is my personal feeling: It is well known that any dedicated compiled program, be it C, C++, Pascal, or other, usually benefit from increased execution speed compared to e.g. scripts. But there is a tradeoff in terms of flexibility vs. e.g. awk, perl esp. when it comes to text analysis and processing, and adapting / modelling algorithms, for which those were specifically targeted / designed.
I'd be very interested in any results comparing execution times of your C++ with an equivalent awk script, as they both will use the same regex system calls.

Last edited by RudiC; 03-01-2018 at 04:57 AM..
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# 16  
Quote:
Originally Posted by RudiC
This is my personal feeling: It is well known that any dedicated compiled program, be it C, C++, Pascal, or other, usually benefit from increased execution speed compared to e.g. scripts. But there is a tradeoff in terms of flexibility vs. e.g. awk, perl esp. when it comes to text analysis and processing, and adapting / modelling algorithms, for which those were specifically targeted / designed.
I'd be very interested in any results comparing execution times of your C++ with an equivalent awk script, as they both will use the same regex system calls.
I hadn't seen this post, else I'd have responded sooner...

I'm not sure how to set a timer within the awk program to just time the replacing time itself, so the results will be based on the programs opening/searching for the key/replacing text/closing.

The word 'ad' was used as it has a long definition and is close to the beginning of the file (less search time).

The timer program:
Code:
#!/bin/mksh
#
# Run:
#
# $ ./bench.sh '<program> <parameters>' <number of iterations> 
#
# Ex.:
#
# $ ./bench.sh 'lat ad' 1000
#

echo "\nRunning \""$1"\" for" $2 "iterations.\n\nPlease wait...\n"

i=0

time while [ $i -le $2 ]; do /home/user/scripts/$1; i=$(($i + 1)); done

The results:

Awk (regex):
1000x @ 2m08.22s real 2m04.66s user 0m05.01s system

C++ (regex):
1000x @ 15.24s real 0m13.44s user 0m01.53s system (8.4x faster than Awk)

C++ (custom search and replace - I'll post this code on the forum)
1000x @ 3.37s real 0m02.54s user 0m00.62s system (4.5x faster than C++ regex)


Timed within the programs themselves and only timing the search and replace process:

C++ (regex)
1000x @ 12.26s real 0m05.82s user 0m00.00s system
Ram used: 3mb

C++ (custom)
1000x @ 1.66s real 0m01.66s user 0m00.00s system
Ram used: > 1mb
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