What is the proper format string for float?

I would like to print a float without unnecessary characters. 0.2, 1.25, 0.02, but in case of lot of digits, I would like to cut the last digits: 1.234 to 1.23 %f, %.2f is not good I think

Answer 1

[Dasharath Gulvady]

If you are looking for a way to round off the decimal values, see the below thread:

http://stackoverflow.com/questions/4211371/how-to-show-certain-number-of-decimal-digits

[Mr M.]

The problem is that %.2f is not good for me, since I dont want to show unnecessary zeros! For example 0.50 instead of 0.5. But 0.45 should be 0.45

Answer 2

[Guillaume]

There is no formatting option that does exactly what you want. You could switch to using '%g' instead of '%f', this does not print trailing zeros, but the precision is then the number of significant digits instead of the number of digits after the decimal point. Furthermore '%g' switches to exponential notation if the magnitude of the number is too big or too small.

For the examples, you've given:

sprintf(n, '%.4g')

works

[Walter Roberson]

%.2g rather than %.4g for the posted requirements.