CMPT 102
Introduction to Scientific
Computer Programming
Course Organization
© Janice Regan, CMPT 102, Sept. 2006
0
CMPT 102: Introduction to Scientific
Computer Programming
 Monday, Wednesday, Friday 9:30-10:20
 Textbook:

C Program Design for Engineers
Authors: Jeri R. Hanly, Elliot B. Koffman
 Additional References:

Engineering Problem Solving with C, 3rd edition
Author: Delores M. Etter

The C Programming Language
Authors: B. W. Kernighan, D. M. Ritchie
© Janice Regan, CMPT 102, Sept. 2006
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Class web-site
 All the information discussed today and more
can always be found on the class web-site
 To find the class web site go to
http://www.cs.sfu.ca/CourseCentral
 Select Course Home pages
 Select the Homepage for CMPT 102
 Course Central is also a useful link to
abundant information useful to students
taking a computing science course
© Janice Regan, CMPT 102, Sept. 2006
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http://www.cs.sfu.ca/CourseCentral
© Janice Regan, CMPT 102, Sept. 2006
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Course selection page
Click
here to go
to
CMPT10
2 website
© Janice Regan, CMPT 102, Sept. 2006
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CMPT 102 Website
© Janice Regan, CMPT 102, Sept. 2006
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My availability
© Janice Regan, CMPT 102, Sept. 2006
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Exams Dates, Course Evaluation
© Janice Regan, CMPT 102, Sept. 2006
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Exams and Evaluation
© Janice Regan, CMPT 102, Sept. 2006
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Evaluation
 Assignments: 30%
 Weekly Quizzes: 15%
 No quiz in week of midterm, week of
Thanksgiving or week of Remembrance day
 Lab Problems: 5%
 Practice Problems: no credit
 Midterm Examination: 15%
 Final Examination: 35%
© Janice Regan, CMPT 102, Sept. 2006
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Assignments
 Four assignments
 Each assignment worth 7.5% of your course
grade
 Assignments are to be completed individually
 Problems similar to the assignments will
appear on the midterm and the final.
 Help is available during weekly lab hours
 Complete solutions will be posted
© Janice Regan, CMPT 102, Sept. 2006
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Lab Problems
 Four short lab problems
 Each lab problem is worth 1.25% of your
final grade
 Practice Problems: no credit BUT valuable
experience that will be useful when
completing lab problems and assignments
© Janice Regan, CMPT 102, Sept. 2006
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Quizzes
 During each Wednesday’s lecture, you will be
asked to answer one question based on material
covered in the lab exercises that week.
 You will be asked to write a short concise
paragraph of 10-15 sentences, explaining a
concept or method, or a short piece of code.
 You will be given 10-15 minutes to answer.
 Your answer will be graded out of 17 (each quiz is
worth 1.7% of your final grade)
© Janice Regan, CMPT 102, Sept. 2006
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Midterm and Final




One 50 minute in class midterm
One 3 hour final examination
35% short answer problems
65% longer problems that utilize several
important concepts and require
integration of those concepts.
 A sample exam, including solutions, will
be posted two weeks before the midterm
and two weeks before the final exam
© Janice Regan, CMPT 102, Sept. 2006
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Assignments, Labs, Solutions
© Janice Regan, CMPT 102, Sept. 2006
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Important Dates
© Janice Regan, CMPT 102, Sept. 2006
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Assignments
 At least two weeks before the due date the
assignment will be posted on the website





Assignments must be completed individually
Assignments will require you to combine and use
many concepts and tools you have learned
Assignments will be much more demanding than lab
problems or practice problems
Complete solutions to all assignments will be posted
Information of proper preparation of assignments and
lab problems is available on the class website.
© Janice Regan, CMPT 102, Sept. 2006
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Labs
 On or before Friday of each week problems will
be posted for the next week. These problems
will be identified as

Lab Problems: To be completed individually or in a
small group (up to four students)


Practice Problems: A chance to use a new idea in a
simple application, before you need to integrate
multiple ideas into assignments.



Submitted for grading
Collaboration is encouraged
Not submitted for grading
Complete solutions to all problems will be posted
© Janice Regan, CMPT 102, Sept. 2006
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Grading Information
 Assignments and Lab Problems should be:
 submitted electronically using the submission server
 submitted in hard copy to the 102 drop box
 Bonus points (10%) are available for submitting
assignments more than 72 hours early
 No late assignments or lab problems will be
accepted
 Unofficial grades will be available on GradeBook

Login: your SFU computer ID, your student number
as password. Find link on Course Central
© Janice Regan, CMPT 102, Sept. 2006
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Where to submit assignments: 1
© Janice Regan, CMPT 102, Sept. 2006
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Where to submit assignments: 2
Submission
drop boxes
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Required Readings, Notes
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Readings and Notes
© Janice Regan, CMPT 102, Sept. 2006
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Academic Honesty
© Janice Regan, CMPT 102, Sept. 2006
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Academic Honesty
Read the
policy
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Getting Started
 If you have not already done so activate
your SFU computing account (CCN,
Campus Computing Network account.)
 Use your own machine at home, or go to the
assignment lab (AQ 3145)
 Email regarding the class will be sent to your
Campus Account, so check it regularly
 Steps to activate your account …
© Janice Regan, CMPT 102, Sept. 2006
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Activating your CCN account (1)
Select mySFU
© Janice Regan, CMPT 102, Sept. 2006
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Activating your CCN Account (2)
Select Apply for ID, the follow the instructions.
You will need your student ID and your TeleReg PIN
© Janice Regan, CMPT 102, Sept. 2006
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Computing Science
Instructional Labs (CSIL)
 The CSIL LINUX lab is available for your use at
all times beginning in the second week of
classes. (ASB 9838)
 At particular times the instructor and/or TA will
be available in the lab to answer your questions.


Instructor:
TA:
 .
Mon. 1:30-3:00 PM,
Tue: 9:00-10:30 AM
Tue: 10:00 – 10:30 AM
TBA
© Janice Regan, CMPT 102, Sept. 2006
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Finding CSIL labs: 1
© Janice Regan, CMPT 102, Sept. 2006
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Finding CSIL labs: 2
CSIL Labs
© Janice Regan, CMPT 102, Sept. 2006
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Access to CSIL
 CSIL is protected by a security card
access system
 As a student in a computing science course
you are eligible to have a security access
card for CSIL
 If you are pre-registered your access card
may be picked up from the card office at
traffic and security (there is a $15 refundable
deposit and a $3 processing fee)
© Janice Regan, CMPT 102, Sept. 2006
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CSIL Rules
 Before you can use any of the computers in the
CSIL you must sign and return an ethics form.

By signing the ethics form you indicate that you have
read and agree to abide by the SFU and CSIL
regulations regarding use of computing resources
and computer labs.
 Links to these policies can be found on the class
website or on Course Central
 You can return your ethics forms during next class, or
directly to the computing science main office.
© Janice Regan, CMPT 102, Sept. 2006
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http://www.cs.sfu.ca/CourseCentral
Select to
reach Policies
© Janice Regan, CMPT 102, Sept. 2006
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CSIL page
IMPORTANT
Read the
Policies
Before
Signing
Your
Ethics form
© Janice Regan, CMPT 102, Sept. 2006
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Getting Started in CSIL
 Before you try programming in CSIL read
the information provided for you
 Read the general information pages
 Browse the FAQs,
 Now you are ready to start
 Your CSIL computer ID and password and
the ID an password you use for your SFU
email account.
© Janice Regan, CMPT 102, Sept. 2006
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CSIL page
Read the
general
information
Browse
The
FAQs
© Janice Regan, CMPT 102, Sept. 2006
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Labs and using CSIL
 The computers in CSIL are available 24/7
 At some times your instructor or TA will be
available to answer questions
 At some times OPEN LAB TA’s will be
available to answer questions.
 A list of TA’s presently in the lab will be
posted on the white board in CSIL.
© Janice Regan, CMPT 102, Sept. 2006
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Optional Lab Hours
 Attendance at optional Lab hours is strongly
encouraged

Lab Hours are held in the LINUX area of CSIL labs
 Lab Hours provide an opportunity to work with others
sharing knowledge and experience.
 Lab Hours give you an opportunity to ask the
instructor or TA one on one questions about
problems and assignments.
 Lab Hours help you learn the required concepts one
by one and allow you to ask questions to assure you
understand each one.
© Janice Regan, CMPT 102, Sept. 2006
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Operating System
 In the CSIL labs you will be using
computers that run the LINUX operating
system
 In the first optional lab hours there will be
tutorials on how to use the LINUX
operating system (1 per hour)
 The tutorial will also be posted so you can
try it yourself at another time
© Janice Regan, CMPT 102, Sept. 2006
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Reading Assignment
 Visit and read the information on the class
website
 Be sure you can find





Posted notes
Reading assignments for each lecture
Assignment due dates
Instructions on using the CSIL labs
Instructions on using your own computer for
assignments
 Have any questions ready for next lecture
© Janice Regan, CMPT 102, Sept. 2006
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CMPT 102
Introduction to Scientific
Computer Programming
Chapter 1:
Computer Components
© Janice Regan, CMPT 102, Sept. 2006
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Hardware and Software
 A computer is a machine designed to perform
operations specified with a set of instructions
called a program.
 Hardware refers to the computer equipment.

keyboard, mouse, terminal, hard disk, printer, CPA
 Software refers to the programs that describe
the steps we want the computer to perform.
© Janice Regan, CMPT 102, Sept. 2006
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Computer Hardware
 CPU –

Central processing unit
Internal
Memory
 ALU –

Arithmetic and logic unit
 ROM –

Read only memory
 RAM –

External
Memory
Input
Processor
Output
ALU
Cache/
Memory
Random access memory
CPU
© Janice Regan, CMPT 102, Sept. 2006
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Software: Operating System
 A system of computer programs that control the
interaction of the user and the computer
hardware. Examples: Linux, Windows, QNX,…
 Purposes of the operating system






Controls communication between input and output
hardware and each process running in the computer.
Directs and orders all operations of the computer
Allocates and shares resources (memory,processor…)
Controls access to resources and data (security)
Provides a user interface (UI) and/or graphical user
interface (GUI)
Stores and accesses data and applications
© Janice Regan, CMPT 102, Sept. 2006
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Example: Command Line UI
 Windows Command Prompt
© Janice Regan, CMPT 102, Sept. 2006
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Example: Graphical UI (GUI)
 Windows explorer
© Janice Regan, CMPT 102, Sept. 2006
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Computer Software: Applications
 Application Software (Software Tools)





Word processors (Microsoft Word, WordPerfect, ...)
Spreadsheet programs (Excel, Lotus1-2-3, ...)
Computer games
Communication software (email, chat, web
browser…)
Telecommunication software (VOIP, …)
© Janice Regan, CMPT 102, Sept. 2006
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Computer Software: Languages
 Some Computer Languages
 Machine language (machine instruction set)
 assembly language
 high level languages



C, C++, Ada, Fortran, Basic, Java
Do YOU know of any others?
mathematical computation tools (MATLAB, Mathematica,
...)
 Application software is written using computer
languages.
© Janice Regan, CMPT 102, Sept. 2006
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Machine language
 Each type of processor (like Pentium 4, Athalon,
Z80, …) has its own instruction set
 Each instruction in an instruction set does a
single thing like access a piece of data, add two
pieces of data, compare two pieces of data …
 Each instruction is represented by a unique
number This # may be different for different
instruction sets, but no two instructions in the
same instruction set will have the same #
© Janice Regan, CMPT 102, Sept. 2006
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Machine Language programs
 In machine language a program is a list of
instructions
 Each instruction is represented by a number
 Inside the memory of the computer each
number is represented in binary (as a
constant length string of 1’s and 0’s)
 The long string of 0’s and 1’s is easy for the
computer to understand and very difficult for
a Human to read or write
© Janice Regan, CMPT 102, Sept. 2006
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Assembler
 Assembler languages make it easier for
the programmer.
 Assembler is easier for humans to read/write
 The numbers that identify each of the
instructions in the instruction set are replaced
with mnemonics like ADD, CMP, …
 The code, written using these mnemonics is
written into a text file.
© Janice Regan, CMPT 102, Sept. 2006
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Assembler Programs
 The code for an Assembler program is written
into a text file.
 The computer read 1’s and 0’s not text
 How do we translate to machine readable form?

A computer program called a compiler is used to
translate the text file (called a source file) containing
the assembler code into machine readable code
 The compiler writes a binary file containing the
machine readable code (called an object file)
© Janice Regan, CMPT 102, Sept. 2006
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Programs in High Level Languages
 Assembler is easier to read/write than machine
language. It is still very cumbersome
 High level languages are easier to write than
assembler

The compiler is more complex, but that is a tool you
use, not one you write
 In this course we will learn the language C
 The rest of today's discussion is equally
applicable to C or to any other compiled
language (C++, Fortran, …)
© Janice Regan, CMPT 102, Sept. 2006
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Writing your program
Editor, Type in
your program
Source File
Text saved on hard disk
Compiler
Translate text into
Machine
Readable code
© Janice Regan, CMPT 102, Sept. 2006
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Source files
 Contains the text you type into a text editor
 The text is a program
 The program is a list of instructions written in a
special Human readable language (C)
 The program can be translated, from the Human
readable language (in source file) to a machine
readable language (in object file), by a compiler
 A compiler is a special piece of software used to
translate from source files to object files
© Janice Regan, CMPT 102, Sept. 2006
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Source files
 Source File:
 Write using a text editor like Kate
 Do not write your code using a word
processor like Microsoft Word. A word
processor will save in a special format.
 The compiler reads only text, not special
formats.
 Beware: your text does not differentiate
between a word processor and an editor
© Janice Regan, CMPT 102, Sept. 2006
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Perfect Code? Finding Errors 1
 It is highly unlikely than any of us will always




write perfect code that contains no errors
How do we find errors?
Are there different kinds of errors? Yes
A computer program can contain syntax errors.
semantic errors, or logical errors
When and how can we detect and correct
errors?



Compile errors
Link errors
Run Time Errors
© Janice Regan, CMPT 102, Sept. 2006
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Syntax Errors
 A computer program can contain syntax errors
 A computer language follows simple rules
 how words and punctuation of different types may be
combined.
 In English syntax is similar to grammatical structure
 The compiler for a high level language can
detect errors that break those simple of syntax
(syntax errors)
 Syntax Errors are usually detected at compile
time
© Janice Regan, CMPT 102, Sept. 2006
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Semantic Errors
 A computer program can contain semantic
errors
 Semantics relates to the meaning of the words
in a sentence or a computer language command
 Just like a grammatically correct English
sentence can be nonsense, a syntactically
correct high level computer language command
can also contain semantic errors
 Some semantic errors may be found by the
compiler, some will be found when the program
is linked, some may be found at run time
© Janice Regan, CMPT 102, Sept. 2006
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Logical Errors
 When your program completes but gives
an unexpected answer it usually means
there is a error in the logic in your solution
of the problem
 Logic errors can also cause a program to
fail part way through execution
© Janice Regan, CMPT 102, Sept. 2006
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Writing your program
Editor, Correct
Syntax Errors
Source File
Editor, Type in
your program
Code
Syntax or Semantic Errors, with
Syntactically
Object File
Compiler Generates error syntax
Correct
Compiler
Messages. To help us find
Translation to
Binary,
Or
code
and Correct errors in the
Machine code
machine readable file
semantic
Source File
errors
© Janice Regan, CMPT 102, Sept. 2006
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Perfect Code? Finding Errors 2
 If your code contains compile time errors is it
correct? NOT NECESSARILY
 How do we find the remaining errors?
 Use a tool that does more checks than the
compiler (splint).
 Move on to linking the code to libraries etc.

The linker resolves references, words in your
program than are defined elsewhere
 Errors occur when the definitions cannot be found
 Errors occur when the use of the word does not
correspond to the definition
© Janice Regan, CMPT 102, Sept. 2006
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Linking your program
Correct
Errors
Find Syntax
and
SemanticErrors
Source
File
(Text)
Editor,
Enter
program
Compile
Object
File
(binary)
Code has linker errors
Semantic Errors Reported:
Finds words with no defined meaning.
© Janice Regan, CMPT 102, Sept. 2006
Other Object Files
Libraries …
Linker
Resolves
References
among
object files
Executable File
(load module)
(binary)
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Perfect Code? Finding Errors 3
 If your code compiles and contains no
errors that can be found by the linker (or
splint) is it correct? NOT NECESSARILY
 How do we find the remaining logic and
semantic errors?
 When you run your executable program
 it may not complete (may or may not
generate error message)
 It may complete and give the wrong answer
© Janice Regan, CMPT 102, Sept. 2006
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Loading/Running your program
Editor,
Enter
program
Source
File
(Text)
Correct
Errors
Find Syntax
and some
SemanticErrors
Object
File
(binary)
Compile
Input
data
CPU
output
results
Link Errors Reported:
Other
Object Files
Linker
Resolves
References
Executable File
(binary)
© Janice Regan, CMPT 102, Sept. 2006
Loader
Copies
Executable
And Runs
65
Summary:
Executing a Computer Program
Input data
C language
Program in
Text file
(source file)
Compile
Machine
language
Program
In binary file
(object file)
Link/load
Execute
Program
output
Other
object files
 Compiler
 Converts a source file (containing your human
readable program in C) to and object file (computer
readable binary file)
 Linker
 Converts object program to executable program
© Janice Regan, CMPT 102, Sept. 2006
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Summary: Types of Errors
 Syntax errors
 Errors in syntax, how words are combined and used

reported by the compiler or splint
 Semantic errors
 Errors in the meaning of words,



Reported by the linker (linker errors)
Reported by the compiler (compile time errors)
Found at execution time (run-time errors)
 Logic errors


Errors causing the incorrect results, not reported
Errors causing program failure (run-time errors)
© Janice Regan, CMPT 102, Sept. 2006
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