Ada Programming: Understanding Procedures, Packages, and Data Types, Slides of Aeronautical Engineering

Download Ada Programming: Understanding Procedures, Packages, and Data Types and more Slides Aeronautical Engineering in PDF only on Docsity! General structure of Ada programs with Ada.Text_Io; procedure Hello_Name is --| Last Modified: June 1998 FirstName: String(1..10); begin Ada.Text_IO.Put (Item => ); Ada.Text_IO.New_Line; Ada.Text_IO.Put (Item => ); Ada.Text_IO.Put(Item => "Hello "); Ada.Text_IO.Put(Item => ". Enjoy studying Ada!"); Ada.Text_IO.New_Line; end Hello_Name; Modules – • – • – • • • • • – • • ------------------------------------------------------------------- --| Requests, then displays, user's name --| Author: Michael Feldman, The George Washington University ------------------------------------------------------------------- -- object to hold user's name -- Hello_Name -- Prompt for (request user to enter) user's name "Enter your first name, exactly 10 letters." "Add spaces at the end if it's shorter.> " Ada.Text_IO.Get(Item => FirstName); -- Display the entered name, with a greeting Ada.Text_IO.Put(Item => FirstName); • Procedure Abstracts an operation Package Collects related operations and data types Advantages of modules Procedures Functional abstraction Top-down development Reduced complexity Parallel development Avoid duplication Packages Shared resources Improved productivity • Improved quality docsity.com Procedure "ADA" in giant letters would be written as a monolithic program. Then we look at it when it is broken into procedures. You can see that a procedure only needs to be written once, and can then be invoked as many times as necessary. The resultant shortening of the program is one of the benefits of procedures. Programs and packages packages • First we see how a program to write • Giant_ada_1.adb, giant_ada_2.adb • Package – Collection of resources – Encapsulated in one unit – Ex: Text_IO, Calendar, user-defined • Used for: – Collection of types and constants – Group of related subprograms – User defined types and allowable operation docsity.com Types of statements Input/Output, Assignment, Control statements Input • Get (argument) values variable Put (Item => “Please enter the first number: “); Get (Item => Number1); Types of statements Input/Output, Assignment, Control statements • Skip_Line Put (Item => “Please enter the first number “); Get (Item => Number1); Skip_Line; Put (Item => “Please enter the second number “); Get (Item => Number2); Skip_Line; Please enter the first number 42 10 Please enter the second number 23 When prompting for values from a user, always follow Get with Skip_Line – Argument is a variable that receives input – Value must be same type (e.g., integer) as – Advance to next line, ignoring unused input docsity.com Types of statements Input/Output, Assignment, Control statements Output • Put(Item => “Please enter the first number: “); Get(Item => Number1); Skip_Line; Please enter the first number: 42 Types of statements Input/Output, Assignment, Control statements Put(int_val, Width => positive_integer); Put ("The sum of the numbers is:"); Put (Number1+Number2, Width=>7); New_Line; Put ("The product of the numbers is:"); Put (Number1*Number2, Width=>3); New_Line; Put ("The sum of the numbers is:"); Put (Number1+Number2, Width=>1); New_Line; The sum of the numbers is: 14 The product of the numbers is: 48 The sum of the numbers is:14 • Put (argument) – Print argument – Leave the cursor on the same line • Formatted output docsity.com Types of statements Input/Output, Assignment, Control statements Put(real_val, Fore => positive_integer, Aft => positive_integer, Exp => positive_integer); Put (23.456); Put (23.456, Exp=>0); Put (23.456, Aft=>3, Exp=>0); Put (23.456, Aft=>2, Exp=>0); Put (23.456, Fore=>3, Aft=>3, Exp=>0); ' 2.34560000000000E+01' '23.45600000000000' '23.456' '23.46' ' 23.456' Types of statements Input/Output, Assignment, Control statements variable – Total_Num := Number1 + Number2; • Assignment – Perform calculation and save result in a docsity.com