11.1 Programming Basics: Variable Declaration - Pseudo-code

Objective: Write pseudo-code statements for the declaration of variables.

Variable declaration is the process of reserving memory space in a computer's memory to store data. In pseudo-code, we use a simple statement to indicate the creation and naming of a variable, along with its initial value (if any).

Basic Variable Declaration Syntax

The general syntax for declaring a variable in pseudo-code is:

  DECLARE  AS  [= ];

Where:

• DECLARE: Keyword indicating the start of a variable declaration.
• : The name you choose for the variable (should follow naming conventions).
• : Specifies the type of data the variable will hold (e.g., INTEGER, REAL, STRING, BOOLEAN).
• [= ]: Optional. Specifies an initial value for the variable. If omitted, the variable is uninitialized.

Examples

Here are some examples of variable declarations in pseudo-code:

1. Example 1: Declaring an integer variable.

   Pseudo-code	Explanation
   DECLARE age AS INTEGER;	Declares a variable named 'age' to store whole numbers (integers). It is uninitialized.

2. Example 2: Declaring a real (floating-point) variable with an initial value.

   Pseudo-code	Explanation
   DECLARE price AS REAL = 19.99;	Declares a variable named 'price' to store decimal numbers (real). It is initialized with the value 19.99.

3. Example 3: Declaring a string variable.

   Pseudo-code	Explanation
   DECLARE name AS STRING = "Alice";	Declares a variable named 'name' to store text. It is initialized with the string "Alice".

4. Example 4: Declaring a boolean variable.

   Pseudo-code	Explanation
   DECLARE is_valid AS BOOLEAN = TRUE;	Declares a variable named 'is_valid' to store a true/false value. It is initialized to TRUE.

Important Considerations:

• Variable names should be descriptive and follow the rules of the programming language you are using (e.g., start with a letter, can contain letters, numbers, and underscores).
• Choosing appropriate data types is crucial for efficient memory usage and accurate calculations.
• Initializing variables is good practice, especially if you expect to use the variable's value before it's assigned a value.