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NWhiteJavascript
beginning java script vocab
Term | Definition |
---|---|
Array literals | to list values in a pair of square brackets |
accessing array elements | finding array index's starting at 0 and increasing by one for each element |
multi-dimensional array | having an array within an array |
array constructor | |
accessing nested array elements | similar to accessing array elements just use index and the number of arrays deep you want to go |
boolean literals | true or false |
boolean logical operators | expression1 && expression2 //returns true if both the expressions evaluate to true |
comparison operators | == does just value checking ( no type checking ) , whereas , === does both value checking and type checking . Seeing the examples may make it all clear. It is always advisable that you never use == , because == often produces unwanted results |
code comments | used to increase the readablility of code |
single line comment | Anything on the line following // will be a comment |
multi line comment | Anything between /* and */ will be a comment. |
console.log | prints text to the console |
console.time | starts a timer that lets you know how long an operation takes to happen. |
console.timeEnd | stops the console.time timer |
function definition | a javascript procedure (a set of statements that performs a task or calculates a value) |
function calling | greet("Anonymous"); |
function hoisting | Declaring a function one way "hoists" it to the top of the call |
if statement | It simply states that if this condition is true , do this , else do something else ( or nothing ) |
else | will only get executed if the "if statement" was false |
else if | It will only run if its condition is true, and the previous statement's condition was false |
for loops | looping a fixed number of times |
while loop | looping for an infinite number of times |
do while loops | if you have to loop at least once but unsure of how many times |
random | returns a random number between 0 and 1 |
floor | returns the largest integer less than or equal to a number |
pow | Returns base raised to exponent. |
ceil | returns the smallest interger less than or equal to a number |
PI | |
sqrt | returns the square root of a number |
%modulus | returns the remainder left when dividing the left side with the right side |
isNaN | returns true if the given number is not a number , else returns false |
Basic Arithmic | |
Prefix and Postfix increment/decrement operators | operators that first increase the value of the variable by 1 (increment) or decrease the value of an expression / variable by 1 (decrement) and then return this incremented / decremented value |