how do you format a float to 2 decimals only

I am outputing float values... I guess by default they output with one decimal only. for example:
the output is:
12.3

my desired output is:
12.30

can anyone show me how to format the float so they're at 2 decimal points?
thank you!

A

I guess by outputting you mean you are using the cout object in which case you can use setprecision(2) like this...

cout<<setprecision(2)<<myfloatvariable<<endl;

I get this error when I use <<setprecision(2) :

setprecision:undeclared identifier.......what does it mean?
thanks!

#include <iomanip.h>

int main()
{
cout << fixed << showpoint << setprecision(2);

cout << //output etc.

return 0;

}

I would be sooo helpless without the help!

Thank you!!!