Close and clear sections

I have a matlab code with multiple sections, circa 25 sections.

One question:

1. The same variables are used in all the sections. Is there a possibility to make a section before all the assignment sections with all those variables? And that every section ''loops'' through this part. For example the easy ones like clear all, close all, clc but also values for the stepzise for the (different) differential equations in the sections.

Thanks!!

[Stephen23]

"For example the easy ones like clear all, close all, clc"

should not be hard-coded in scripts or functions.

In any case, you can easily write a function which returns your hard-coded parameters, or define a simple structure which contains all of your parameters, and pass that.