How do I pad a printf to take account of negative signs and variable length numbers?

Question

I\'m trying to output some numbers in a log file and I want to pad a load of floats via the printf function to produce:

 058.0
 020.0
 038.0
-050.0
         


        

Answer 1

The width specifier is the complete width:

printf("%05.1f\n", myVar);  // Total width 5, pad with 0, one digit after .

To get your expected format:

printf("% 06.1f\n", myVar);