Sometimes you want to compare the execution time between two different implementations in your scripts, so to do this easily use the
time built-in shell tool.
First you must know the path of your time shell tool.
$ which time /usr/bin/time
If you use
time directly could have some troubles.
$ time -f %e sleep 4 -f: command not found real 0m0.071s user 0m0.056s sys 0m0.012s
which time result to use it instead.
$ /usr/bin/time -f %e sleep 4 4.00
You'll get the result in seconds.
The structure must be like
/usr/bin/time -f %e YOUR SCRIPT INSTRUCTIONS HERE