ITEC 320
Procedural Programming
Dr. Ray
Lecture 1
Outline
• Welcome
• Intro to the course
• Ada – first steps
Introduction
Syllabus
• R Lectures / Interactive demonstrations
• Office Hours 2:00-3:00 PM MTWF
– Saturday 7:00-8:00PM or Sun. 3:00-4:00
• Website
– www.radford.edu/aaray => ITEC 320
•
•
•
•
D2L for submission
Projects
Homework
Exams
Introduction
Introduction
• On a scale of 1 to 10, how interested are
you in learning a different language?
• How many lines of code did you write for
the largest program you’ve worked on?
• What do you want to learn in this course?
• Share with your neighbor
• Introduce yourselves and answers to the
class
Introduction
Language
s
• What advantages are there to learning a
new computer language?
• What are the some of the reasons for
learning a new language?
• Why is this important?
– Objective C example
Introduction
1970s
• The era of…
• Multiple languages used at the DOD…
• What are some of the problems with using
multiple languages?
• What happens when you use multiple
languages for one project?
Introduction
Solution
• Design competition
Introduction
Result
•
•
•
•
Procedural / OO mixed language
Multi-threaded / generics
Reliability and maintenance
Readability over writability
$line =~ /.{28}(\d\d)-(\d\d)-(\d\d).{8}(.+)$/
Introduction
Difference
s
public class HelloWorld
{
public static void main(String[] args)
{
int x;
x=3;
System.out.println(x);
}
}
with ada.text_io;
with ada.integer_text_io;
procedure hello1 is
x: Integer;
begin
x := 3;
ada.text_io.put_line("Hello World");
ada.integer_text_io.put(x);
end hello1;
Introduction
Java
Ada
First
impressions
• What are your thoughts on what you just
saw?
with ada.text_io;
with ada.integer_text_io;
procedure hello1 is
x: Integer;
begin
x := 3;
ada.text_io.put_line("Hello World");
ada.integer_text_io.put(x);
end hello1;
Introduction
How to
make it
work
• Write / Compile / Execute cycle
• Editors
– vi filename.adb
• Compiler
– gnatmake filename
• Execution
– filename or ./filename (Mac)
Introduction
Types
• Why is it important to know what type of
variable it is that you are using?
• What are the different types of variables
you are familiar with?
Introduction
Informatio
n
• Largest and smallest numbers possible
• Integer add
– ‘first;
– ‘last;
– ‘range;
• Character
– ‘val(65);
– ‘pos(‘A’);
• Boolean
– Boolean’val(0);
– Boolean’pos(true);
Introduction
Extra
types
• Natural
– 0 to Integer’Last --Biggest integer
• Positive
– 1 to Integer’Last
• Chance
– 0.0 to 1.0 --Constrained float
Introduction
More
types
•
•
•
•
Character (8 bit)
Wide_Character (16 bit)
Wide_Wide_Character (32 bit)
Strings
– Arrays of characters
– Fixed length
– 3 types (more later)
Introduction
Conversio
n
• Anything to String
intVar’img
intVar’image
• String to Integer
Integer’val(“12”);
Integer’value(“123”);
• Character conversions
Character’val(65);
Character’pos(‘A’);
Introduction
Output
• Convert non-strings to strings
– Combine strings with the &
• Output and stay on same line
– put( );
• Output and goto next line
– put_line( );
• Enter key
– new_line;
Introduction
Formatting
Output
• width
put(var, width=>2);
– minimum width
• fore
– Minimum number of places before decimal
• aft
– Number of places after decimal
• exp
– Minimum number of places for the exponent
Introduction
Type
checking
• Both sides of assignments must match
• Operands of arithmetic operators must
match
• Must do it all manually
– In Java, int’s will be converted to floats
• Extends to output
– System.out.println how we will miss thee
– ada.integer_text_io.put(3);
–
ada.text_io.put(“Lots
of
typing”);
Introduction
Summary
•
•
•
•
Short day
History of ADA
Basics of the language
Introductory comparison of the languages
Introduction