Eric Siegel

Programming Glossary


variable	Holds values, e.g., integers (int), strings (string) and reals
                (float, double).  Two warnings: (1) declare all variable
		together at the top of a function and (2) assign values before
		using. 

declaration	At the top of the function, state your variables' types.

types		int, float, double, string; arrays thereof

assignment	"x = 5;"  MAKE SURE TO USE  O N E  EQUAL SIGN!

comparison	"(x == 5)"  MAKE SURE TO USE  T W O  EQUAL SIGNS!
                Or, "(x > 5)", etc.
		
loop		Use "for" or "while" to make it repeat a block.

conditional	An if-statement.

boolean		Something that is true or false, e.g., a comparison.

condition       A boolean expression used to control conditionals and loops.

comments	/* Label your code, write yourself a note! */

formatting	Indent stuff nicely, etc.  Compiler ignores it; TAs don't.

nesting		Putting stuff inside other stuff, e.g., a conditional in a loop.

flag		A boolean variable to convey true-false info.  In C, an int.

operators	A built-in function such as *, +, -, /, for, while, if, =

comparison operators include ==, <, <=, >=, !=

function        Something that is called with parentheses, e.g., sqrt().
                Specifically, A portion of code that is designed for
		one mini-task, e.g., draw a line, draw a square,
		compute the square root, or find the largest value.
		In Java, functions are called "methods".


statement	A command line that ends with a semicolon.

expression	Anything that has a value, e.g., "a + b" or "(a == b)" or "c++"

Boolean expressions can be built with && (and) and || (or)

block		Chunk of code between curly braces {}

algorithm	process/routine/method to solve a problem

evaluate	to find the value of an expression

syntax		grammar defining a programming language

compiler error	an error that causes the compiler to produce an error
                message and fail

run-time error	an error that does not disrupt compiling, but causes your
                program to abort with an error message when running, e.g.,
		"segmentation fault" and "floating point exception"     

logic error	an error that the computer never notices, but that you
                notice because your darn program doesn't do what you
		want it to do.

module		A portion of source code that has a specific job, e.g.,
                a module of code to maintain an alphabetical list of names.
		Often, the module is put into its own source code file

class		A portion of source code in an object-oriented programming
                language such as Java; one class per source code file.
		The concepts of object-orient design are outside the
		scope of this course.

nesting		When you put one thing inside another, e.g., a conditional
                inside a loop, a loop inside a conditional, a loop inside
		a loop, etc.

stepwise refinement  The "divide and conquer" strategy to computer programming.
                Start with the main goal, and break it down into subparts.
		Then, break each subpart down into smaller parts.  Once
		you have broken it down into small enough parts, each
		part is programmed as ither a class or a function.  This
		is considered "top-down" design, since the main goal
		is the "high level" goal, and then the designer works her
		way down to the details.

modular decomposition  The design that results from stepwise refinement, since
                your design has been "decomposed" into modules

encapsulation   The physical separation of different subtasks, e.g., into 
                separate classes, source code files or modules.

conceptual abstraction	The ability for people to create different points of
                view on a design, depending on the relevant degree of detail.
		Through stepwise refinement, one traverses multiple
		levels of abstraction.  Similarly, in digital circuitry,
		the details of creating AND, OR and NOT gates with transistors
		is at one level of abstraction, and use of 1-ADD circuits
		to build a full adder is at a higher level of abstraction.

email: evs at cs dot columbia dot edu