It is important to understand the difference between a "script" and a "real program", and which languages are appropriate for each.
Scripts tend to be small (no more than a few hundred or a few thousand lines of code) and do not do any significant computation of their own.
Instead, scripts run "real programs" to do most of the computational work. The job of the script is simply to automate and document the process of running programs.
As a result, scripting languages do not need to be efficient and are generally interpreted rather than compiled. ( Interpreted language programs run an order of magnitude or more slower than equivalent compiled programs, unless most of their computation is done by built-in, compiled subprograms. )
Real programs may be quite large and may implement complex computational algorithms. Hence, they need to be fast and as a result are usually written in compiled languages.
If you plan to use exclusively pre-existing programs such as Unix commands and/or add-on application software, and need only automate the execution of these programs, then you need to write a script and should choose a good scripting language.
If you plan to implement your own algorithm(s) that may require a lot of computation, then you need to write a program and should select an appropriate compiled programming language.