Scalar Variables

Section 1.7 Scalar Variables

Variables need not be declared in MATLAB, one simply makes an assignment.

>> x = 5;
>> y = 10;
>> z = x + y;

When variable are assigned, they show up in the workspace window, along with their value and class (built-in debugger!)

>> x = 10; y = 10;
>> z = x + y;

Can you name a variable "cos"? If so, what is the effect of doing so?

Rules for variable names (similar to C):

Can contain only letters, digits, and the underscore ’_’

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Must begin with a letter (not true for C, e.g., _var)

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Case sensitive (AA Aa aA aa are all different variables)

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Avoid using built-in function names. You can actually use such a name, but then you can no longer use the function (i.e. cos, sin, exp, sqrt, etc.)

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Can be up to 63 characters long… but we know that using such a variable name would be poor style!

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Table 1.15. Managing Variables

Function	Description
`clear`	Removes all variables from memory 🔗
`clear x y z`	Removes only the variables `x`, `y`, `z` 🔗
`who`	Displays a list of variables in memory 🔗
`whos`	Displays a list of variables in memory, along with their size and other info 🔗

The Workspace Window also shows you a visual picture of the variables that you have assigned.