Unable to do calculation and get print out to label - iphone

Question

I'm doing the following code when they hit the calculate button in my app:
float sqft = ([textfield1.text floatValue]);
float thick= ([textfield2.text floatValue]);
float cos = ([textfield3.text floatValue]);
float eff = ([textfield4.text floatValue]);
float num = ((thick*.5)*sqft)/eff;
float cost = (num*cos);
float costft = (cost/sqft);
label1.text = [NSString stringWithFormat:#"%2.f",num];
label2.text = [NSString stringWithFormat:#"%2.f",cost];
label3.text = [NSString stringWithFormat:#"%2.f",costft];
When I do this the labels only return zeros. I have set the labels to maually be strings just to see if it was a delegation thing but I can't figure out why my formulas return zeros only

Answer 1

The problem is with the way you have used %2.f in your code,
%2.f gives you the rounded value of the answer in 2 number format. If any of your answer is less than or equals to 0.5 . then you get 0 as the answer.
now it should work
float sqft = ([textfield1.text floatValue]);
float thick= ([textfield2.text floatValue]);
float cos = ([textfield3.text floatValue]);
float eff = ([textfield4.text floatValue]);
float num = ((thick*.5)*sqft)/eff;
float cost = (num*cos);
float costft = (cost/sqft);
label1.text = [NSString stringWithFormat:#"%2f",num];
label2.text = [NSString stringWithFormat:#"%2f",cost];
label3.text = [NSString stringWithFormat:#"%2f",costft];

Answer 2

Its working proper at my end . But in one case you will get ZERO value when your value is 0.786676 like that..
textfield1.text = #"123.89";
textfield2.text= #"123.00";
textfield3.text= #"123.7";
textfield4.text= #"123";
float sqft = ([textfield1.text floatValue]);
float thick= ([textfield2.text floatValue]);
float cos = ([textfield3.text floatValue]);
float eff = ([textfield4.text floatValue]);
float num = ((thick*.5)*sqft)/eff;
float cost = (num*cos);
float costft = (cost/sqft);
NSLog(#"Num : %#",[NSString stringWithFormat:#"%2.f",num]);
NSLog(#"Cost : %#",[NSString stringWithFormat:#"%2.f",cost]);
NSLog(#"Costft : %#",[NSString stringWithFormat:#"%2.f",costft]);
Output
Num : 62
Cost : 7663
Costft : 62

Answer 3

You want to limit the digits after the decimal point to two - that is why you are using .2f, right? If so, you should use this #"%.2f"
Just try this:
label1.text = [NSString stringWithFormat:#"%.2f",num];
label2.text = [NSString stringWithFormat:#"%.2f",cost];
label3.text = [NSString stringWithFormat:#"%.2f",costft];