1. CS1101: Programming Methodology http://www.comp.nus.edu.sg/~cs1101/ http://www.comp.nus.edu.sg/~cs1101/

2. Week 3: Numerical Data and OOP Basics  Last week:  Chapter 1: Intro to OOP and S/W Development  Chapter 2: Getting Started with Java  DrJava  CourseMarker  This week:  Take-home lab #1  Chapter 3: Numerical Data  Chapter 4: Defining Your Own Classes – Part 1  Next week:  Chapter 4: Defining Your Own Classes – Part 1 (cont’d)  Chapter 5: Selection Statements © CS1101 (AY2009-2010 Semester 1)Week3 - 2

3. Reminder  Have you read the relevant chapters and PowerPoint files BEFORE coming to this lecture?  Have you been filling your Progress Chart? © CS1101 (AY2009-2010 Semester 1)Week3 - 3

4. Chapter 3 Numerical Data Any questions on Chapter 3? We’ll skip GregorianCalendar class. © CS1101 (AY2009-2010 Semester 1)Week3 - 4

5. What are the answers? (1/2) (int) 23.82 = 30 % 7 = 30 / 7 = 30.0 / 7 = 30 / 7.0 = 30.0 / 7.0 = (double) 30 / 7 = 30 / (double) 7 = (double) (30 / 7) = © CS1101 (AY2009-2010 Semester 1)Week3 - 5 +

6. What are the answers? (2/2) 1 + 2 + 3 + "Java" = "Java" + 1 + 2 + 3 = "Java" + (1 + 2 + 3) = 1 + "Java" + 2 + 3 = 1 + 2 + "Java" + 3 = © CS1101 (AY2009-2010 Semester 1)Week3 - 6 +

7. Temperature Conversion The following is the formula to convert temperature in degree Fahrenheit to Celsius:  C = (5/9) × (F – 32) Download “Ch3TemperatureConvert.java” and test it.  Why doesn’t it work?  Can you correct the program?  Note: This type of error is very common! © CS1101 (AY2009-2010 Semester 1)Week3 - 7

8. Loan Calculator Let’s study the development of this program. © CS1101 (AY2009-2010 Semester 1)Week3 - 8

9. Take-home lab assignment #1 It has been released. Deadline is next Monday, 31 August 2009, 23:59hr. Any questions? © CS1101 (AY2009-2010 Semester 1)Week3 - 9

10. Java API Documentation (1/2) A very important website  http://java.sun.com/javase/6/docs/api/ http://java.sun.com/javase/6/docs/api/ © CS1101 (AY2009-2010 Semester 1)Week3 - 10 Bookmark it!

11. Java API Documentation (2/2) It’s impossible to cover everything about a standard (built-in) class, so you need to look it up yourself. For example, in take-home lab #1, you need to look for these yourself: Exercise 1: What is the maximum integer value in Java? Exercise 3: What is the method in Scanner class to read the user’s input as a line of text? Exercise 4: What is the appropriate method in Math class to compute the hypothenuse? © CS1101 (AY2009-2010 Semester 1)Week3 - 11

12. Chapter 4 Defining Your Own Classes – Part 1 Let’s go to Chapter 4. © CS1101 (AY2009-2010 Semester 1)Week3 - 12

13. Summary for Today What are numerical data types? Performing computation on numerical data Some standard (built-in) classes  DecimalFormat  Scanner  Math  Random API documentation page How to define and use your own class (to be continued next week) © CS1101 (AY2009-2010 Semester 1)Week3 - 13

14. Announcements/Things-to-do Take-home lab #1 deadline: 31 August 2009, Monday, 23:59hr. To prepare for next week’s lecture:  Read Chapter 4 (again) and Chapter 5 and their PowerPoint files before you come for lecture.  Do Quick Check questions in Chapter 4. Check out the answers (on CS1101 website) yourself. To prepare for next week’s discussion session:  Download “week4_discussion_qns.pdf” from module website, “CA – Discussion”.  Do the questions before you attend your discussion session. © CS1101 (AY2009-2010 Semester 1)Week3 - 14

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