JavaScript - Determining Factors

i am using trying to use the following code to find the prime factors of a number:
Code:

function prime(number){//returns prime factors of input in array
	test=2;//number to test divisibility
	factor_count=0//counts number of factors
	factors=[];
	while (test<number){
		quotiant=number/test
		quotiant_round=Math.floor(quotiant);
		if(quotiant==quotiant_round){//number is divisible by test
			factor_count=factor_count+1;
			factors[factor_count]=test;
			number=number/test;
			test=test-1;//counters adding one
		}
		test=test+1;
	}
	return (factors)
}

running it manually in chromes JavaScript console i get:
prime(2)=[]
prime(4)=[undefined, 2]
prime(8)=[undefined, 2, 2]
prime(6)=[undefined, 2]
prime(9)=[undefined, 3]
prime(27)=[undefined, 3, 3]
prime(18)=[undefined, 2, 3]
i am using the = to separator my input from its output

I need some help putting the factors of a number (y) into an array

For example if y = 20: [1, 2, 4, 5, 10, 20]

Once I have this, I can use it to factor a quadratic:

(ax = c)(bx = d)

if c = 3 and d = 5 then I could check if 1c was a decimal, if 20d was a decimal and then vice versa

Basically, I can use these numbers to see if b or d is a whole number and if it isn't, try the next one.

If none of them are, then I can do y(ax + c)(bx + d)

Thanks!

Basically I want to factor a number and select the two closest numbers to the middle of the factors

for example:

20 factors to 1, 2, 4, 5, 10, 20

I want it to return 4 and 5

If the number is has an odd number of factors (has to be a perfect square) I want it to select the middle number and say it twice

for example:

64 factors to 1, 2, 4, 8, 16, 32, 64

I want it to return 8 and 8

Would I use an array or what?

My code should probably look like:

PHP Code:
x = //Factors array
y = //number of items in x
if (/*y is even*/){
i = y/2
i2 = i+1
a = [i]
b = [i2]
}
else{
i = //somehow the center number?
i2 = i
a = [i]
b = [i2]
} 

Hello All,

I am a JS newbie and I'm wondering if there a way to figure out the sentence from which a word has been highlighted.

Essentially, when a user selects a word or a phrase, I should output the sentence from which it's been selected.

Is this possible with JS or with any server side languages?

- Pallav

Some background might better help my actual problem. Feel free to address either with any relevant insights.

While attempting to create a greasemonkey script in FF2 (don't ask), I discovered that the "let" statement was causing my code to fail. After confirming that this statement has been available since FF2 (js engine 1.7) https://developer.mozilla.org/en/New_in_JavaScript_1.7, I became curious as one determines their javascript engine in FF.

IE has a way to inspect the jscript engine, ala http://msdn.microsoft.com/en-us/libr...8VS.80%29.aspx , but I couldn't find anything similar for FF. Feel free to list links for testing engines in other browsers, too.

I can't use irc at work, so it's good to know this place is still around for numb-nuts like me. :-)

Many, many thanks (in-advance).