Frequently Asked Questions  

The Founders and Foundations of Computer Science - Video and notes of talks given by a few of the most significant figures in Computer Science.

ML

• Additional information and manuals
  • Draft of Programming in ML and examples by Robert Harper

  • A Gentle Introduction to ML by Andrew Cumming

• Debugging programs - Source level debugging in Poly/ML

• Pasting

  • Do not use the right button click to Paste in immediate execution mode. The pasted text is ignored.

  • Use the menu Edit | Paste instead.

Java

• Online Tutorial
• Input/Output
• Math
• Parameter passing

Input/Output

• How to do output in Java? Java uses System.out.print( ) rather than C++ cout. All standard types can be output. Generally only one data type can be printed at a time. To output Hello World:

System.out.print("Hello World");

in C++ it would be:

cout << "Hello World";


The simplest is to use:

System.out.print( expr );

where expr is a string, int, float, etc. expression. To output several expressions in one output statement use concatenation (i.e. the + operator), for example to output the value of IP and op variables seperated by a tab and terminated by a new line use:

System.out.print(IP + "\t" + op + "\n");

• Why no output appears? No output is displayed until a Carriage return/Line feed is printed. This can be done by:

System.out.println();

or by outputting a "\n".

Math

• How are math functions used? Take the absolute value of x in Java by:

x = Math.abs(x);

Parameter Passing

• How are parameters passed in Java? See discussion on threadsafe, how Java passes parameters, etc. by IBM developers.