sprintf padding front of string with spaces, what to do?

seidleroni · Guest

Hi Everyone,

When I use the following line:

sprintf(s, "%7.3f", fValue);

If the fValue has less than 3 digits in front of the decimal place, then it is padded with spaces. Here is an example:

fValue: New Value:
"1234.123" "1234.123"
"123.123" "123.123"
"12.123" " 12.123"
"1.123" " 1.123"
".123" " .123"

Should I just change the line to be:
sprintf(s, "%0.3f", fValue); ? What is the best way to get rid of the leading spaces?

Thanks

Ttelmah · Guest

Unfortunately, this is going to be difficult:
In standard 'C', this is solved by using a sign character
In C, if the leading character of the field declarator, is _not_ a sign character, then a space _will_ be added to the start of the number output. The only reason it disappears in the top two lines, is that you have run out of width in the output field, so it gets thrown. So far then, CCS is working 'right'.
So, in normal C if you use:

Seidleroni · Guest

In my code, I can use the line

ttelmah · Guest

No, that is probably perfectly acceptable (though see below for the caveat). Anything up to 4.3, should also work. The standard behaviour, is to print in a field at 'least x wide', where 'x' is the value in front of the DP. If the output is greater than 'x', then the field is automatically expanded.The padding 'space', is only added if the output is less than the specified field width.
I'd be possibly 'chary' of using '0', since this has the special meaning of 'use zero as the padding character', but 4.3, (your minimum width is four characters, with .000), ought to work in any C. Smile

I was assuming you had some need for the field to not drop below 7 characters, so could not use this method.

Best Wishes