Quadratic Formula Solver Qustion

[mikelowe]

Ok, so I am a bit new with the iPhone SDK and this is getting frustrating. I am trying to build an application where the user types in the values of a,b, and c for a quadratic equation and it gives them x. so far, this is what I have

- (IBAction) solve {
	
	//a is the string, afield is the text field, ia is double
	a = afield.text;	
	ia = [a doubleValue];
	
	b = bfield.text;
	ib = [b doubleValue];
	
	c = cfield.text;
	 ic = [c doubleValue];	
	
	ix1 = (-ib + sqrt((ib*ib)-4*(ia*ic)))/2*ia;
	x1 = [NSString stringWithFormat:@"%i", ix1];
	x1field.text = x1;
	
	ix2 = (-ib - sqrt((ib*ib)-4*(ia*ic)))/2*ia;
	x2 = [NSString stringWithFormat:@"%i", ix2];
	x2field.text = x2;
	
	
	x2field.text = [NSString stringWithFormat:@"%d", ix2];
	
	root = ((ib*ib)-4*(ia*ic))/2*ia;
	
	if (root == 0) {
	
		UIAlertView* alertView = [[UIAlertView alloc] initWithTitle:@"Oh No!" message:@"There is no real answer to this equasion." delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
		[alertView show];
		[alertView release];
		
	}
	
}

I don't get any errors, but the x1field and x2field values are always 0. I'm pretty sure the answer is something simple. Help would be greatly appreciated

[mer]

You're using "%i" and "%d" in your string formatter, both of which are expecting integers, but ix1 and ix2 look like they're doubles. Try changing them to "%f".

[mikelowe]

Originally Posted by mer

You're using "%i" and "%d" in your string formatter, both of which are expecting integers, but ix1 and ix2 look like they're doubles. Try changing them to "%f".

Thanks! that works perfectly.

[!_UK@$]

I really doubt this works perfectly, because you have missing the parenthesis at the end of the assignment:
ix1 = (-ib + sqrt((ib*ib)-4*(ia*ic)))/2*ia;
The "2*ia" should be like this: "(2*ia)", because if you omit the parenthesis, it firstly divide the result from the left expression by 2, and then it multiply it all with 'ia'.

[mikelowe]

good call. Havent touched this project in a while. Didn't test it thoroughly.