compsci 105 ss 2005 principles of computer science lecture 1 lecturer: santokh singh
TRANSCRIPT
CompSci 105 SS 2005
Principles of Computer Science
Lecture 1
Lecturer: Santokh Singh
Introduction to the CourseLecturerCourse OverviewTeaching StylePolicies
Numbers in the ComputerMagnitude PrefixesRepresenting information in a machineBinary representation of integers
“Welcome to COMPSCI 105 ”
Santokh’s Contact Details:
Office: Room 303 488
4th floor new science bldg. (City)
Telephone: 82283
Email: [email protected]
http://www.cs.auckland.ac.nz/~ssin080
- Santokh
Office Hours
• See COMPSCI 105SS 2005 web pages for details and updates.
• Brief discussions before and after all lectures.
COMPSCI 105 SS Team 2005
Lecturer & Supervisor:
Santokh Singh
Tutor:
Cheung Ling Kelly Yu
Introduction to the Course
Lecturer
Course Overview
Teaching Style
Policies
Numbers in the Computer
Magnitude Prefixes
Representing information in a machine
Binary representation of integers
COMPSCI 101 :
Principles of Computer Programming
COMPSCI 105 :
Principles of Computer Science
Data Structures
Algorithms
Introduction to the Course
Lecturer
Course Overview
Teaching Style
Policies
Numbers in the Computer
Magnitude Prefixes
Representing information in a machine
Binary representation of integers
Summer School
• More intense
• Fewer Lecture Hours
• Better Staff/Student Ratio
• Better Weather (hopefully ;-)
The Course Book
• One free printed and bound copy per student
The Textbook
Carrano and Prichard, “Data Abstraction and Problem Solving with JAVA: Walls and Mirrors”, Addison-Wesley, 2004.
(Can also use 2001 Edition, shown above)
Available from UBS
Lectures
• Outlines
• Readings
• Focus Questions
Tutorials
• 9 Assessed
• 1 “Optional”
• Worth 8%
• Outlines, Readings, Focus Questions
Assignments
Due on Friday of:
Week 2
Week 3
Week 5
Worth 17% total
Test and Exam
Test, Week 4, Worth 10%
Exam, Worth 65%
Class Reps
• Need one from each of the tutorials.
• Their names and contact details will be posted on the course web page.
Introduction to the Course
Lecturer
Course Overview
Teaching Style
Policies
Numbers in the Computer
Magnitude Prefixes
Representing information in a machine
Binary representation of integers
2,000 meters
2 kilometers
2 x 103 meters
Peta- 1015 1,000,000,000,000,000
Tera- 1012 1,000,000,000,000
Giga- 109 1,000,000,000
Mega- 106 1,000,000
Kilo- 103 1,000
Milli- 10-3 .001
Micro- 10-6 .000001
Nano- 10-9 .000000001
Pico- 10-12 .000000000001
Femto- 10-15 .000000000000001
How long does light take to travel 30cm?
• About a millisecond (10-3)• About a microsecond (10-6)• About a nanosecond (10-9)• About a picosecond (10-12)• About a femtosecond (10-15)
Speed of light is approximately 3 x 108 m/s.
Introduction to the Course
Lecturer
Course Overview
Teaching Style
Policies
Numbers in the Computer
Magnitude Prefixes
Representing information in a machine
Binary representation of integers
Human Symbols (Characters)
1 2 3 4 5 6 7 8 …
A B C D E F G H …
£ * ∞ ® ™ § ¶ & …
♠ ♣ ♥ ♦ ♪ ♫ ☺ ♂ …
Binary Symbols (Bits)
• 0 1
int i = 2173;
float f = 3.14159285;
String s = “Anything!”;
One Bit
• Two Patterns:
1
0
Two Bits
• Four Patterns:
01 11
00 10
Three Bits
0 0 1
0 1 0
0 0 0
0 1 1
1 0 1
1 1 0
1 0 0
1 1 1
• Eight Patterns:
Three Bits
0 10
1 00
0 00
1 10
0 11
1 01
0 01
1 11
• Eight Patterns:
n Bits
• 1 bit 2 things
• 2 bits 4 things
• 3 bits 8 things
• 4 bits 16 things
• 5 bits 32 things
• n bits
How many bits do I need to assign a unique bit pattern to everyone in the class?
How many bits do I need to assign a unique bit pattern to everyone in the class?
20 121 222 423 824 1625 32
26 6427 12828 25629 512210 1024211 2048
How many bits for x things?
Need b bits, where
2b-1 < x and
2b ≥ x
Exponents and Logarithms
be = x
logbx = e
How many bits for x things?
log2x
Course Book
Notes for this section are in the Course Book:-
• Pages 62 - 64: Numbers in the Computer
• Pages 65 - 92: Data Representations
Late Enrolment Fee
if ( not_enrolled_by_deadline){ liable_to_pay_$50_extra_fee (“not covered by Student Loans”);
}.
// Welcome again & enjoy COMPSCI 105// SS 2005.