C error with an integer?

[TomMacs]

All right here's an odd error that I can't seem to figure out. I'm using KDevelop 3. Here's the compilers error report:
4.09999999999999975575093458246556110680103302002e-1' cannot be used as a function

and here's the code thats giving the problem:

// Inductance of secondary coil
float SIuH;
SIuH = pow(STT * (SD / 2), 2) / 9*(SD / 2) + 10 * SH;
cout << "Inductance of Secondary Coil (mH): " << SIuH << endl;

hmmm, I'm stuck.

[bryan.6]

could it be something dealing with the pow... does that return a double? i wouldn't think that would screw up anything though...

do you get this exact error ( about 5 ) EVERY time you run the program, or does the number in the error change with the inputs?

[TomMacs]

I haven't thought about changing the format of the equation, but what I have done was experiment with different number values. They all came in with the same result and error message. I tired long double and double. When I get home though I plan on proceeding with what you said, I'll play around with the format of the equation and pow(). I do know that this one specific equation does result in a very large decmial point.

[cybertron]

Incidentally, in my experience pow is very slow if you're just squaring something. In a program I wrote once I got at least a 200% speed increase by just changing my squaring from using pow to simply multiplying the thing by itself. That would also eliminate pow as a source of the problem.

[bwkaz]

What are STT, SD, and SH? Are they #defined to something, or are they all variables? If they are #defined, what are they #defined to? Does it help to make them "const double"s or "const long double"s?

[madcompnerd]

You can also always just rewrite POW, for ints it's like a 4 line function.
I dunno how you compiled it as c code, I dunno how to use iostream from c, but I compiled it as c++ code and it worked.