Printing floats, not doubles, with printf functions
Posted on 2004-03-30
In MSDN, the format of printf states that %f is for printing doubles.
The format of scanf, on the other hand, makes the difference between %f for floats and %lf for doubles.
Is there a way I can print a float variable on the screen so that only its correct value is printed? That is to say, it is well-known that only 7 digits of any float number are relevant, thus, for example, 957.3456 is okay but 19923.3456 is not (the latter should be 19923.35). But if I assign the latter to some float variable, or make some operation with this result, and then printf it (or fprintf, or sprintf) it will show all the digits.
So, here is the question: if I'm using a log file and print numbers into it with fprintf(LOG_FILE,"%f",fX), how should I change is in order to get in the file the same value that I'm getting in Visual Studio's watch? That is, if I watch the value of fX during the debug, the value is different from that written into LOG_FILE, because of what I said above.