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Hi!
i dont know what is the difference between the 2 masks (the result
on visual c++ 2010 is the same):
and this mask too (what 0* means?)Code:
sprintf(msg, "Number %2.2d",10);
sprintf(msg, "Number %02.2d",10);
Thanks!!Code:
sprintf(msg, "Number %0*d",10);
Try numbers other than ten and you might just find out yourself.
Like what? i tried others too but with or without 0 (2.2 / 02.2) i got the same result. this is not a homework or something that i want you to do for me... If i'm asking here is because i really want to know the difference. So if you will say "try others to find yourself", please, don't answer my post, this is for people who want to learn and exchange experiences...
anyway, thank you!
And i still dont know the difference, so please, if anyone knows just tell me.
So did you actually try 100,1000,10000,100000 and so on?
If you want to learn, you do the typing, compiling, running the code, observing the results.
Then (and only then), do you post your code and results, and ask for more clarification.
We're not going to just write a whole test program just for you.
You can find your answers here: printf - C++ Reference
i have tried with this:
And still the same result for both.Code:
sprintf(msg, "Teste %02.2d",100);
sprintf(msg, "Teste %02.2d",100000);
sprintf(msg, "Teste %02.2d",100000000);
sprintf(msg, "Teste %2.2d",100);
sprintf(msg, "Teste %2.2d",100000);
sprintf(msg, "Teste %2.2d",100000000);
1 - And again, i dont want you to write a program for me, i just want to know whats the difference between 2 masks(o2.2 and 2.2).
2 - I looked at the reference before and i understood that the 0 is used for left padding... Buf even if i dont use the 0 i still got the padding of 0 on the .2 number...
i just want to know something like "ITS FOR PADDING" or "ITS FOR THIS OR THAT", dont a program write if you dont want to your "majesty" ^^
Ummm... why don't you try changing all those 2s to 8s and see what happens?Quote:
Originally Posted by RLeePlusPlus
Really... rather than getting all ........ed off, do some real experimenting.
i still got the same results, with or without the '0' preceding the width... Just for information, i'm using VS2010 express
thank you
So, now you have your answer... It doesn't matter (in VS2010).
FFS go and read the link I posted, specifically the documentation about the width specifier!Quote:
Originally Posted by RLeePlusPlus
Once you do that, it will be clear that you will see a difference using a single digit value, like 7.
Why it doesn't matter in VS 2010? in GCC/GPP i have to put the 0?
Because that's the way the libraries are written.Quote:
Originally Posted by RLeePlusPlus
Really... I'm no more telepathic than you are... I have no idea why programmer A decides one thing and programmer B decides another.
Just accept these things as they are, use them, and get on with it.
man, you really S U CK S... telepatic? Its not about to accept and use! Its about WHY IS DIFFERENT or IS REALLY DIFERENT? What a stupid reply... leave this for who want to discuss. You should be banished for answer questions like this.
and don't reply this, put your idead in you A SS
Oh my... yet another short fuse who can't deal with reality.
Look sport... Some compilers and libraries do things differently... only the authors of those libraries know why and for the most part they're not talking. What do you want me to tell you? The only available answer is that we don't know why... we are thus left to work with what is before us.
You can talk about it till you're blue in the face... nothing is going to change that basic fact.
Now... get that foul temper of yours under control, or get lost.
Can you stop feeding conslusions of his own poor experimentation back at him as though they were answers? It irks me almost as much it must irk him.Quote:
Originally Posted by CommonTater
He's stupidly listening to your interpretation of his results instead of actually reading the documentation, and is incorrectly concluding that Visual Studio is broken, which it is not.
RLeePlusPlus they do give different results, you're just not reading the documentation to see what values would make it give different results. I've already told you one answer and yes it will give a different result in Visual Studio.
Now stop wasting everyone's time and actually read the link posted. If you don't understand part of what it says then ask a specific question about that part.
Of course VS is broken... but this probably isn't one of the ways... :DQuote:
Originally Posted by iMalc
The point was that there are indeed differences in behaviour between libraries. Supposedly C-99 standardizes much of this, but Microsoft is not adhering to that standard as it would break a whole lot of Windows code if they did.
I already told him to try his experiment again changing his 2 character field widths to 8... where he would clearly see what happens... But he perists, probably without even trying it.
Now, when he is told in a slightly comedic way that we don't know why some things are different... because we were not privy to the library programmer's decision making... he blows a gasket, with you right behind him.
I'm sorry... but really guys... this is just a little over the top!
1 - I read the documentation before i post this question and i read it again when you said to. specifically on the width it says:
(number) Minimum number of characters to be printed. If the value to be printed is shorter than this number, the result is padded with blank spaces. The value is not truncated even if the result is larger. * The width is not specified in the format string, but as an additional integer value argument preceding the argument that has to be formatted.
right before it, on "flags" it says:
0 - Left-pads the number with zeroes (0) instead of spaces, where padding is specified (see width sub-specifier).
So.. back to my question, with or without 0 i got the same results.... The number is padded with 0s.
So, i asked, why? And i don't want to know "why this compiler do this wat and that one do taht way", i just want to know if is only this difference that makes it the way it is! Simple like that, i dont want to take anyone's time..
And by the way CommontTater, i'm not hot fuse but answer questions with "telepatic" ? Come on, respect.
I said that i tried it, and get answers like yours is over the top...
It doesn't get much more complicated than what you've been told.
The idea of integer precision is pretty silly so the C library makes out integer precision to be "pad with zeros". Integer width is different: basically, that measure counts the number of columns that an integer should take up, and it works like precision does, except instead of padding with zeros, it pads with white space. When the precision or width is smaller than the digit length of the number, no padding occurs.
You can use them in combination for formatted output. Use width to make tabular columns, and use precision to pad zeros to numbers. It's pretty easy to play with. :)
I apologize if I've been short with you before. I was trying to be helpful, but hopefully this is more so.Code:#include <stdio.h>
#include <time.h>
#include <stdlib.h>
int main()
{
int i, prec, w;
srand(time(NULL));
for ( i = 0; i < 120; i += 5 ) {
prec = rand()%12;
w = rand()%20;
printf("%*.*d\n", w, prec, i);
}
return 0;
}
/* output - yours may differ slightly:
0
0000005
000000010
15
20
00000025
0030
00000000035
0000040
045
0000000050
55
0000060
000065
0000000070
000000075
80
85
0090
95
100
000000105
00000110
000115
*/
edit - And, if you make a width like this "%05d" for example; like the documentation says, it will pad the width with zero instead of space. So that is why the zero flag is supported.
I understand... so 0 is used to specify the pad when you put just the width, right? like "%03d". When you use width.precision, the precision of the integer will be always padded with 0s...
So, there is no need for "%02.2d" because .2 will guarantee that the result is shorter than the precision it will be padded with 0s. Am i right?
Thank you for your answer!Code:
sprintf(msg, "%05d",10); //[00010]
sprintf(msg, "%5d",10); //[ 10]
sprintf(msg, "%05.5d",10); //[00010] No reason for 0, because .5 will pad with 0's, right?
sprintf(msg, "%5.5d",10); //[00010]
You understand well. :) You're welcome.
"%2d" means print the integer value 2 spaces to the left of the last character printed in the string, ".2" means to 2 decimal places. "Decimal place" does not mean "zeroes".
Mmmmmmm, should've read more thread. *prepares self for condescension
Look at this. See how many things I'm wrong about? SEE?!