round function

[madshov]

Hi,

I need to make a function, that takes as input a double. This should be rounded so it always has a decimal precision of 3:

12.1234 = 12.123
12.1235 = 12.124
12.12 = 12.120
0 = 0.000

Is this possible? The output is going to be written to a file, so it's ok to convert the double to a string and let the function return this string, if it makes the problem easier. Does anybody know a nice and clean way to make this function, or do I need to go ugly??

[JosAH]

Why not simply use the format "%.3f" when you print those numbers to the file?

kind regards,

Jos

[madshov]

But can I make a fixed length. e.g. 8 characters with blankspaces i front:
" 23.233"

[Banfa]

"%8.3f"

but note if the number will not fit in 8 characters the 8 will be ignored for example

10000.001

[Banfa]

Also try googling "printf format codes"

[jorba101]

If you do "%08.3f" the number will get filled with as many "0" in the front as needed to get it 8 numbers.

But still you'll have to check for the number not to be bigger than certain value, so that it does not get larger than 8.

See http://www.acm.uiuc.edu/webmonkeys/b...12.html#printf for further detail