Formatting Ouput with Punctuation (Commas)

[MikeCopeland]

Given: a value of 17234987, is there a (good) way to format it for
output as 17,234,987? I would have thought that stream i/o would
support such formatting, but I can't find anything that seems to show
how to do it.
Please advise. TIA


---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

[Öö Tiib]

On Monday, 8 August 2016 04:14:09 UTC+3, MikeCopeland wrote:
> Given: a value of 17234987, is there a (good) way to format it for
> output as 17,234,987? I would have thought that stream i/o would
> support such formatting, but I can't find anything that seems to show
> how to do it.
> Please advise. TIA

You have to use 'std::locale' and 'std::put_money' read up on those
for details. Teaser example:

#include <iostream> // for std::cout
#include <iomanip> // std::put_money and other utilities

int main(int argc, char **argv)
{
const int amount = 1000000; // in cents

std::cout.imbue(std::locale("en_US.UTF-8"));

std::cout << std::showbase << std::put_money(amount) << '\n';
}

That should output ...

$10,000.00

[MikeCopeland]

Not quite wqhat I'm looking for: I'm not working with money data, but
large integer values. With your solution, there's no way to format
integers >999 with punctuation. Am I missing something?

[Öö Tiib]

Indeed, you missed my remark that it was example and my suggestion to read
up on the things involved. You hate to read? OK I will complete it
for you:

#include <iostream> // for std::cout
#include <iomanip> // std::put_money and other utilities

int main(int argc, char **argv)
{

const int amount = 17234987; // in cents

std::cout.imbue(std::locale("ja_JP.UTF-8"));

std::cout << std::put_money(amount) << '\n';
}

Done, 17,234,987 exactly as specified. Was it that hard?

[Alf P. Steinbach]

UTF-8 for byte streams is not supported in Windows.

So that's very non-portable code. ;-)

Also, consider `num_put`. Mike's example indicates that it's just a
number, not a monetary amount.


Cheers!,

- Alf

[Öö Tiib]

On Monday, 8 August 2016 11:56:39 UTC+3, Alf P. Steinbach wrote:
> On 08.08.2016 03:31, Öö Tiib wrote:
> > On Monday, 8 August 2016 04:14:09 UTC+3, MikeCopeland wrote:
> >> Given: a value of 17234987, is there a (good) way to format it for
> >> output as 17,234,987? I would have thought that stream i/o would
> >> support such formatting, but I can't find anything that seems to show
> >> how to do it.
> >> Please advise. TIA
> >
> > You have to use 'std::locale' and 'std::put_money' read up on those
> > for details. Teaser example:
> >
> > #include <iostream> // for std::cout
> > #include <iomanip> // std::put_money and other utilities
> >
> > int main(int argc, char **argv)
> > {
> > const int amount = 1000000; // in cents
> >
> > std::cout.imbue(std::locale("en_US.UTF-8"));
> >
> > std::cout << std::showbase << std::put_money(amount) << '\n';
> > }
> >
> > That should output ...
> >
> > $10,000.00
> >
>
> UTF-8 for byte streams is not supported in Windows.
>
> So that's very non-portable code. ;-)

UTF-8 is right now 83% - 87% of all web content ... so if Windows
can't even byte stream that then what is it useful for? Perhaps
something like "English_Australia.1252" will work there then. :-)

>
> Also, consider `num_put`. Mike's example indicates that it's just a
> number, not a monetary amount.

Perhaps 'num_put' is indeed best. I wondered how he can't find
*anything* in stream I/O and so I just pointed direction. If he
wants to use I/O utilities then he has quite lot to read there.

[Rick C. Hodgin]

On Sunday, August 7, 2016 at 9:14:09 PM UTC-4, MikeCopeland wrote:
> Given: a value of 17234987, is there a (good) way to format it for
> output as 17,234,987? I would have thought that stream i/o would
> support such formatting, but I can't find anything that seems to show
> how to do it.
> Please advise. TIA

auto amt1 = amount % 1000;
auto amt2 = (amount % 1000000) / 1000;
auto amt3 = (amount % 1000000000) / 1000000;

if (amount < 1000)
cout << amt1;
else if (amount < 1000000)
cout << amt2 << "," << amt1;
else if (amount < 1000000000)
cout << amt3 << "," << amt2 << "," << amt1;

Something like that.

Best regards,
Rick C. Hodgin

[Scott Lurndal]

MikeCopeland <mrc...@cox.net> writes:
> Given: a value of 17234987, is there a (good) way to format it for
>output as 17,234,987? I would have thought that stream i/o would
>support such formatting, but I can't find anything that seems to show
>how to do it.
> Please advise. TIA

Use 'snprintf'. The ' formatting flag will use the grouping
character from the locale to group digits appropriately.

http://pubs.opengroup.org/onlinepubs/7908799/xsh/fprintf.html

[Öö Tiib]

*Bzzzzt*, wrong, but thank you for playing.
What it will output on case of amount = 17004087?

[Rick C. Hodgin]

I don't know how in C++ to make it work with values < 100 the lower
amounts. It will produce weird things like "1,23,456" for 1,023,456".
I'd have to use what I know. :-)

int amount = 1023045;
char buf1[4], buf2[4];
sprintf(buf1, "%03d", amount % 1000);
sprintf(buf2, "%03d", (amount % 1000000) / 1000);

auto amt1 = amount % 1000;
auto amt2 = (amount % 1000000) / 1000;
auto amt3 = (amount % 1000000000) / 1000000;

if (amount < 1000)
cout << amt1;
else if (amount < 1000000)

cout << amt2 << "," << buf1;
else if (amount < 1000000000)
cout << amt3 << "," << buf2 << "," << buf1;

[Rick C. Hodgin]

I appreciate your kindness in pointing out my mistake. It reveals much
about your character.

> What it will output on case of amount = 17004087?

17,4,87.

[Alf P. Steinbach]

On 08.08.2016 15:54, Öö Tiib wrote:
> On Monday, 8 August 2016 11:56:39 UTC+3, Alf P. Steinbach wrote:
>> On 08.08.2016 03:31, Öö Tiib wrote:
>>> On Monday, 8 August 2016 04:14:09 UTC+3, MikeCopeland wrote:
>>>> Given: a value of 17234987, is there a (good) way to format it for
>>>> output as 17,234,987? I would have thought that stream i/o would
>>>> support such formatting, but I can't find anything that seems to show
>>>> how to do it.
>>>> Please advise. TIA
>>>
>>> You have to use 'std::locale' and 'std::put_money' read up on those
>>> for details. Teaser example:
>>>
>>> #include <iostream> // for std::cout
>>> #include <iomanip> // std::put_money and other utilities
>>>
>>> int main(int argc, char **argv)
>>> {
>>> const int amount = 1000000; // in cents
>>>
>>> std::cout.imbue(std::locale("en_US.UTF-8"));
>>>
>>> std::cout << std::showbase << std::put_money(amount) << '\n';
>>> }
>>>
>>> That should output ...
>>>
>>> $10,000.00
>>>
>>
>> UTF-8 for byte streams is not supported in Windows.
>>
>> So that's very non-portable code. ;-)
>
> UTF-8 is right now 83% - 87% of all web content ... so if Windows
> can't even byte stream that then what is it useful for?

It's not Windows, it's standard library implementations for Windows, and
it's not byte streams, it's the C++ narrow streams.

The proper standard-conforming portable way in C++ to produce or consume
UTF-8 is to use wide streams (they're designed to convert to/from
external bytes), with a properly translating buffer.

To be honest I think the whole C++ i/o design sucks. More than miss
Lovelace. And I'm not talking about Ada Lovelace.

> Perhaps
> something like "English_Australia.1252" will work there then. :-)

Maybe.

The only two standard locale names in C++ are "C" and "", where the
former is the C and C++ default locale, and the latter denotes the
user's default locale.

This is part of the low pressure area effect noted above.

>> Also, consider `num_put`. Mike's example indicates that it's just a
>> number, not a monetary amount.
>
> Perhaps 'num_put' is indeed best. I wondered how he can't find
> *anything* in stream I/O and so I just pointed direction. If he
> wants to use I/O utilities then he has quite lot to read there.

Yes, I wish the infamous Someone™ could come up with something better…


Cheers!,

- Alf

[Good Guy]

On 08/08/2016 04:36, MikeCopeland wrote:

Not quite wqhat I'm looking for: I'm not working with money data, but large integer values. With your solution, there's no way to format integers >999 with punctuation. Am I missing something? --- 

Try the method given in this video.  You'll need to adapt the technique to suit your project.

<https://www.youtube.com/watch?v=n9_3MbIjQbE>

--

With over 350 million devices now running Windows 10, customer satisfaction is higher than any previous version of windows.

[red floyd]

On 8/8/2016 10:15 AM, Good Guy wrote:
> On 08/08/2016 04:36, MikeCopeland wrote:
>> Not quite wqhat I'm looking for: I'm not working with money data, but
>> large integer values. With your solution, there's no way to format
>> integers >999 with punctuation. Am I missing something? ---
>
> Try the method given in this video. You'll need to adapt the technique
> to suit your project.
>
> <https://www.youtube.com/watch?v=n9_3MbIjQbE>
>
>

Dude, please don't post that ugly HTML here. Plain text ASCII, please.

[Good Guy]

this one works:

// main.cpp

#include <iomanip>
#include <locale>
#include <iostream>
#include <sstream>

using namespace std;

class AndysCommaNumPunct : public numpunct <char>
{
protected:
    virtual char do_thousands_sep() const
    {
        return ',';
    }

    virtual string do_grouping() const
    {
        return "\003";
    }
};

template <class T>
string AndyFormatWithCommas(T value)
{
    stringstream ss;
    locale AndyCommaLoc( locale(), new AndysCommaNumPunct() );
    ss.imbue(AndyCommaLoc);
    ss << setprecision(2) << fixed << value;
    return ss.str();
}

int main()
{
    int anInt = 31235;
    
    cout << "int:    " << AndyFormatWithCommas(anInt) << endl;
    
    float aFloat = 31235.47987;
    
    cout << "float:  " << AndyFormatWithCommas(aFloat) << endl;
    
    long aLong = 987654321;
    
    cout << "long:   " << AndyFormatWithCommas(aLong) << endl;
    
    double aDouble = 987654321.126456789;
    
    cout << "double: " << AndyFormatWithCommas(aDouble) << endl;
    
    return 0;
}

Source: <https://www.youtube.com/watch?v=9SubQGhfgJQ>

[red floyd]

On 8/8/2016 10:53 AM, Good Guy wrote:
[html redacted]

WTF do you have against plain text, dude?

[Good Guy]

Actually there is a wonderful tool called Google that has most of the answers - some good and some not so good but it requires some effort to make them work.

--

If you want to filter all of my posts then please read this article:
<https://support.mozilla.org/en-US/kb/organize-your-messages-using-filters>
In step 7 select "Delete"

[red floyd]

On 8/8/2016 2:21 PM, Good Guy wrote:
[red floyd wrote] WTF do you have against plain text, dude?

>
> Actually there is a wonderful tool called Google that has most of the
> answers - some good and some not so good but it requires some effort to
> make them work.

Do you even READ the posts you are replying to?

[Alf P. Steinbach]

It's an ad bot.

Cheers!,

- Alf

[Geoff]

On Sun, 7 Aug 2016 18:13:57 -0700, MikeCopeland <mrc...@cox.net> wrote:

> Given: a value of 17234987, is there a (good) way to format it for
>output as 17,234,987? I would have thought that stream i/o would
>support such formatting, but I can't find anything that seems to show
>how to do it.
> Please advise. TIA
>
>

I don't know if this is a "good" way and it's Microsoft C++ and CRT dependent
but I wrote this quite a while ago and have not had to touch it since:

//
//============================================================================
// Turns an unsigned long long into a string with localized separators
//============================================================================
//
std::string LocalizeNumber(unsigned long long number)
{
std::string str;
TCHAR temp[64], num[64];

_ui64toa_s(number, temp, sizeof temp, 10);
GetNumberFormat(LOCALE_USER_DEFAULT, 0, temp, NULL, num, sizeof num);
str.assign ( num );
return str;
}

[red floyd]

On 8/8/2016 9:06 PM, Alf P. Steinbach wrote:
>
> It's an ad bot.

Doh!!!!

How could I be so stupid to miss that! Thanks, Alf!

[Vir Campestris]

It is? But it's far too stupid for that...

Back to the OP - remember that when you and I see 123.456 it's a hundred
and something, to some nationalities that full stop is a thousands
separator and the value is over a hundred thousand... number formatting
brings nightmares. Nearly as bad as dates.

Andy