10.3: Script Basics
- Page ID
- 132174
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The Standard Header
Every MATLAB script in this course starts with three cleanup commands and a comment block:
clear removes all workspace variables. clc clears the command window. close all closes open figure windows. Together they ensure every run starts from a clean state — a reproducible result. A script that behaves differently depending on what you ran before is not an engineering tool.
Variables, Comments, and Semicolons
The semicolon suppresses output to the command window. Without it, every assignment prints its value. Units belong in comments, not variable names — write m = 1000; % kg, not m_kg = 1000.
Sections
%% marks a section. Sections let you run one block at a time (Ctrl+Enter) and document the structure: