Re: New package proposal: Math_Calculus

ok thank you. i thought it would need to be more complicated ... Johannes Schlueter wrote:

On Friday 16 May 2003 11:24, you wrote:

could you please enlighten, at least, me.

I'll try ;-)

I remember deriving and integration from university, but really have to say that your code seems only to be for a very special purpose. I can not tell the class: please derive this function f(x) = x^2 + x, with x=<some value>. Actually that's what i expected.

For doing this you're code would look like function some_math($x) { return $x*$x + $x // Your formula translated to PHP code } // create object with the function defined above $calculus = new Calculus('some_math'); // Calculate the derivation at <some value> echo $calculus->derivate(<some value>); This would print the value of the derivation at <some value>, at university you would have derivated first symbolic f(x) = x^2 + x => f'(x) = 2x + 1 and then calculated f'(x) for your value: f'(<some value) = 2*<some value> but doing this symbolic calculations is a bit harder than just looking for the numeric value of the derivation at a given point, what my class does - it just calculetes the value of f'(x) at the given position not the complete f'(x) function. By using a PHP function for implemnting the formula I can use nearly every function you might want to derivate or integrate. I hope this helpes otherwise I would need to fetch my math books and a dictionary to copy the definitions here (ok, you're German, so I wouldn't need the dicitonary *g*), but I hope I don't need to do this :-)

(Actually i really hate that i dont need all the stuff from university anymore)

I heared this sentence quite often - maybe I should stop going to university ;-) johannes

-- Wolfram ... opensource @ vision:produktion ... http://opensource.visionp.de ... translating template engine .... http://sf.net/projects/simpletpl ... authentication system .... http://sf.net/projects/auth