Formatting decimal places

[Andrew]

I trying to format my output to display a set number of decimal
places. I have been trying to use the <iomanip> setprecision(), but
that will only display the total number of digits. Can someone please
help me???? Thanks.

[Marcin Kalicinski]

Re: Formatting decimal places

Uzytkownik "Andrew" <admckni@hqcnsg .navy.mil> napisal w wiadomosci
news:8e7fb04b.0 404200701.78f63 8bb@posting.goo gle.com...[color=blue]
> I trying to format my output to display a set number of decimal
> places. I have been trying to use the <iomanip> setprecision(), but
> that will only display the total number of digits. Can someone please
> help me???? Thanks.[/color]

Check out boost::format.

Marcin

[John Harrison]

Re: Formatting decimal places


"Andrew" <admckni@hqcnsg .navy.mil> wrote in message
news:8e7fb04b.0 404200701.78f63 8bb@posting.goo gle.com...[color=blue]
> I trying to format my output to display a set number of decimal
> places. I have been trying to use the <iomanip> setprecision(), but
> that will only display the total number of digits. Can someone please
> help me???? Thanks.[/color]

You have to set the 'float mode' to fixed. E.g.

#include <iostream>

#include <iomanip>

using namespace std;

int main()

{

cout << fixed << setprecision(1) << 1.23456789 << '\n';

cout << fixed << setprecision(2) << 1.23456789 << '\n';

cout << fixed << setprecision(3) << 1.23456789 << '\n';

cout << fixed << setprecision(4) << 1.23456789 << '\n';

cout << fixed << setprecision(5) << 1.23456789 << '\n';

}

john

[Julie]

Re: Formatting decimal places

Marcin Kalicinski wrote:[color=blue]
>
> Uzytkownik "Andrew" <admckni@hqcnsg .navy.mil> napisal w wiadomosci
> news:8e7fb04b.0 404200701.78f63 8bb@posting.goo gle.com...[color=green]
> > I trying to format my output to display a set number of decimal
> > places. I have been trying to use the <iomanip> setprecision(), but
> > that will only display the total number of digits. Can someone please
> > help me???? Thanks.[/color]
>
> Check out boost::format.
>
> Marcin[/color]

Boost is OT in this forum.

[Mike Wahler]

Re: Formatting decimal places


"Andrew" <admckni@hqcnsg .navy.mil> wrote in message
news:8e7fb04b.0 404200701.78f63 8bb@posting.goo gle.com...[color=blue]
> I trying to format my output to display a set number of decimal
> places. I have been trying to use the <iomanip> setprecision(), but
> that will only display the total number of digits. Can someone please
> help me???? Thanks.[/color]

#include <ios>
#include <iomanip>
#include <iostream>

int main()
{
double d(3.14);

std::cout << std::fixed << std::setprecisi on(4)
<< d << '\n';

return 0;
}

Output:

3.1400


-Mike

[Siemel Naran]

Re: Formatting decimal places

"John Harrison" <john_andronicu s@hotmail.com> wrote in message
news:c63g5t$7da a2$1@ID-
[color=blue]
> You have to set the 'float mode' to fixed. E.g.[/color]
[color=blue]
> cout << fixed << setprecision(1) << 1.23456789 << '\n';
>
> cout << fixed << setprecision(2) << 1.23456789 << '\n';[/color]

The float mode is sticky, so you don't have to set it in each line, though
setting it is harmless and often a good idea for clarity if we're fixing
fixed and scientific output in the same program.

cout << fixed;
cout << setprecision(1) << 1.23456789 << '\n';
cout << setprecision(2) << 1.23456789 << '\n';

[bartek]

Re: Formatting decimal places

Julie <julie@nospam.c om> wrote in news:408545AE.C 7FE7FDC@nospam. com:
[color=blue]
> Marcin Kalicinski wrote:[color=green]
>>
>> Uzytkownik "Andrew" <admckni@hqcnsg .navy.mil> napisal w wiadomosci
>> news:8e7fb04b.0 404200701.78f63 8bb@posting.goo gle.com...[color=darkred]
>> > I trying to format my output to display a set number of decimal
>> > places. I have been trying to use the <iomanip> setprecision(), but
>> > that will only display the total number of digits. Can someone please
>> > help me???? Thanks.[/color]
>>
>> Check out boost::format.
>>
>> Marcin[/color]
>
> Boost is OT in this forum.[/color]

Why don't you like boost?

Strange, but I've seen other people not using it *just because* (i'm not
counting compiler issues that might arise with boost).
Why - I wonder.

cheers!
b

[Julie]

Re: Formatting decimal places

bartek wrote:[color=blue]
>
> Julie <julie@nospam.c om> wrote in news:408545AE.C 7FE7FDC@nospam. com:
>[color=green]
> > Marcin Kalicinski wrote:[color=darkred]
> >>
> >> Uzytkownik "Andrew" <admckni@hqcnsg .navy.mil> napisal w wiadomosci
> >> news:8e7fb04b.0 404200701.78f63 8bb@posting.goo gle.com...
> >> > I trying to format my output to display a set number of decimal
> >> > places. I have been trying to use the <iomanip> setprecision(), but
> >> > that will only display the total number of digits. Can someone please
> >> > help me???? Thanks.
> >>
> >> Check out boost::format.
> >>
> >> Marcin[/color]
> >
> > Boost is OT in this forum.[/color]
>
> Why don't you like boost?[/color]

I did not express my preference for Boost in my response.

I was expressing (rather tersely) that a reference to Boost is off-topic in
this forum when there is an existing and preferred solution in C++ language.

[bartek]

Re: Formatting decimal places

Julie <julie@nospam.c om> wrote in news:4085574C.C E8A5E68@nospam. com:
[color=blue]
> bartek wrote:[color=green]
>>
>> Julie <julie@nospam.c om> wrote in news:408545AE.C 7FE7FDC@nospam. com:
>>[color=darkred]
>> > Marcin Kalicinski wrote:
>> >>
>> >> Uzytkownik "Andrew" <admckni@hqcnsg .navy.mil> napisal w wiadomosci
>> >> news:8e7fb04b.0 404200701.78f63 8bb@posting.goo gle.com...
>> >> > I trying to format my output to display a set number of decimal
>> >> > places. I have been trying to use the <iomanip> setprecision(),
>> >> > but that will only display the total number of digits. Can
>> >> > someone please help me???? Thanks.
>> >>
>> >> Check out boost::format.
>> >>
>> >> Marcin
>> >
>> > Boost is OT in this forum.[/color]
>>
>> Why don't you like boost?[/color]
>
> I did not express my preference for Boost in my response.
>
> I was expressing (rather tersely) that a reference to Boost is
> off-topic in this forum when there is an existing and preferred
> solution in C++ language.
>[/color]

Sorry, I overreacted to your post.

Although, I don't think that mentioning boost is off topic here at all.
Just as it's not off topic to direct an (confused?) individual to other
(more appropriate?) newsgroups, isn't it?

cheers!
b

[Dave Moore]

Re: Formatting decimal places

admckni@hqcnsg. navy.mil (Andrew) wrote in message news:<8e7fb04b. 0404200701.78f6 38bb@posting.go ogle.com>...[color=blue]
> I trying to format my output to display a set number of decimal
> places. I have been trying to use the <iomanip> setprecision(), but
> that will only display the total number of digits. Can someone please
> help me???? Thanks.[/color]

I doubt you have stated things correctly, unless your version of the
STL is broken ... an example usually helps clear up such
misunderstandin gs. The problem is that you also need to use the
manipulator std::fixed to specify that the field has a fixed number of
decimal places. Thus the following code

#include <iostream>
#include <iomanip>

int main() {
std::cout << std::setprecisi on(3);
std::cout << 1.0 << ' ' << 12.47 << ' ' << 16.89567 << std::endl;
std::cout << std::fixed;
std::cout << 1.0 << ' ' << 12.47 << ' ' << 16.89567 << std::endl;
return 0;
}

should produce:
1 12.47 16.9 // think about it .. you'll figure out why
1.0000 12.4700 16.8957

HTH, Dave Moore

[David Harmon]

Re: Formatting decimal places

On Tue, 20 Apr 2004 08:45:50 -0700 in comp.lang.c++, Julie
<julie@nospam.c om> wrote,[color=blue]
>Marcin Kalicinski wrote:[color=green]
>>
>> Uzytkownik "Andrew" <admckni@hqcnsg .navy.mil> napisal w wiadomosci
>> news:8e7fb04b.0 404200701.78f63 8bb@posting.goo gle.com...[color=darkred]
>> > I trying to format my output to display a set number of decimal
>> > places. I have been trying to use the <iomanip> setprecision(), but
>> > that will only display the total number of digits. Can someone please
>> > help me???? Thanks.[/color]
>>
>> Check out boost::format.
>>
>> Marcin[/color]
>
>Boost is OT in this forum.[/color]

Where OT = "On Topic"

[Julie]

Re: Formatting decimal places

David Harmon wrote:[color=blue]
>
> On Tue, 20 Apr 2004 08:45:50 -0700 in comp.lang.c++, Julie
> <julie@nospam.c om> wrote,[color=green]
> >Marcin Kalicinski wrote:[color=darkred]
> >>
> >> Uzytkownik "Andrew" <admckni@hqcnsg .navy.mil> napisal w wiadomosci
> >> news:8e7fb04b.0 404200701.78f63 8bb@posting.goo gle.com...
> >> > I trying to format my output to display a set number of decimal
> >> > places. I have been trying to use the <iomanip> setprecision(), but
> >> > that will only display the total number of digits. Can someone please
> >> > help me???? Thanks.
> >>
> >> Check out boost::format.
> >>
> >> Marcin[/color]
> >
> >Boost is OT in this forum.[/color]
>
> Where OT = "On Topic"[/color]

Nope. OT is the accepted "Off Topic".

From one of my other responses:
[color=blue]
> I was expressing (rather tersely) that a reference to Boost is off-topic in
> this forum when there is an existing and preferred solution in C++ language.[/color]

[Dave Moore]

Re: Formatting decimal places

admckni@hqcnsg. navy.mil (Andrew) wrote in message news:<8e7fb04b. 0404200701.78f6 38bb@posting.go ogle.com>...[color=blue]
> I trying to format my output to display a set number of decimal
> places. I have been trying to use the <iomanip> setprecision(), but
> that will only display the total number of digits. Can someone please
> help me???? Thanks.[/color]

Sorry .. after submitting I realized that the line

std::cout << std::setprecisi on(3);

in my previous post should have been

std::cout << std::setprecisi on(4);

I guess that is why they give you that "review before posting" option
at google 8*) .. sorry for any confusion.

[Jeff Schwab]

Re: Formatting decimal places

Julie wrote:[color=blue]
> David Harmon wrote:
>[color=green]
>>On Tue, 20 Apr 2004 08:45:50 -0700 in comp.lang.c++, Julie
>><julie@nospam .com> wrote,
>>[color=darkred]
>>>Marcin Kalicinski wrote:
>>>
>>>>Uzytkowni k "Andrew" <admckni@hqcnsg .navy.mil> napisal w wiadomosci
>>>>news:8e7fb0 4b.0404200701.7 8f638bb@posting .google.com...
>>>>
>>>>>I trying to format my output to display a set number of decimal
>>>>>places. I have been trying to use the <iomanip> setprecision(), but
>>>>>that will only display the total number of digits. Can someone please
>>>>>help me???? Thanks.
>>>>
>>>>Check out boost::format.
>>>>
>>>>Marcin
>>>
>>>Boost is OT in this forum.[/color]
>>
>>Where OT = "On Topic"[/color]
>
>
> Nope. OT is the accepted "Off Topic".
>
> From one of my other responses:
>
>[color=green]
>>I was expressing (rather tersely) that a reference to Boost is off-topic in
>>this forum when there is an existing and preferred solution in C++ language.[/color][/color]

Not a fan of irony, I see.

Why is it OT even to mention boost? Also, if you know of a "preferred
solution," why was it worth your time to criticize someone else, but not
worth your time to present the solution?

[David Harmon]

Re: Formatting decimal places

On Tue, 20 Apr 2004 10:41:14 -0700 in comp.lang.c++, Julie
<julie@nospam.c om> wrote,[color=blue]
>[color=green]
>> I was expressing (rather tersely) that a reference to Boost is off-topic in
>> this forum when there is an existing and preferred solution in C++ language.[/color][/color]

Boost is a collection of solutions in the C++ language. Widely accepted
and frequently preferred. Not in any way off-topic that I can see.
It does happen to be the wrong answer to the question of this thread,
but that's a different matter entirely.