Umal-qura university

Lab # 3

OBJECTIVES OF THE LAB
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In this lab, we will get an understanding of the following topics:

• 
  Making Functions
  
• 
  Control Structures
  
• 
  Relational Constructs
  
• 
  Logical Constructs
  
• 
  Branching Constructs
  
• 
  Looping constructs
  

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1. MAKING FUNCTIONS

A function can be created by the following syntax:

function [output1,output2,...] = function_name(input1,input2,...)

A function is a reusable piece of code that can be called from program to accomplish some specified functionality. A function takes some input arguments and returns some output. To create a function that adds two numbers and stores the result in a third variable, type in it the following code:

function add x = 3;
y = 5;
z = x + y
Save the file by the name of add (in work folder, which is chosen by default), go back to the command window and write
>> add
z =
8
You see that the sum z is displayed in the command window. Now go back to the editor/debugger and modify the program as follows
function addv(x,y) z = x + y
Save the above program with a new name addv, go back to the command window and type the following:
>> addv(3, 5)
z =
8
>> addv(5, 5)
z = 10
We have actually created a function of our own and called it in the main program and gave values to the variables (x, y).

Now go back to the editor/debugger and modify the program as follows

function adv(x, y)

%
% This function takes two values as input,
% finds its sum, & displays the result.
% inputs: x & y
% output: z
% Example: addv(3,6)
% Result: z=9
% z = x + y

Save the program with the same name addv, go back to command window, type the following >> help addv

‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ This function takes two values as input, finds its sum, & displays the result. inputs: x & y
output: z
Example: addv(3, 6) Result: z=9
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1.