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5.3 printShowingDecimalPlaces: 2 displays '5.29' instead of '5.30'

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Sebastian Sastre-2

5.3 printShowingDecimalPlaces: 2 displays '5.29' instead of '5.30'

Hi there,

I'm geting this unexpected result from a Squeak 3.9 final 7067 image.

I need to display money values with two digits. Has anybody a sugestion to correctly achieve this?

thanks,

Sebastian Sastre

timrowledge

Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29' instead of '5.30'

On 22-Nov-07, at 10:03 AM, Sebastian Sastre wrote:

Hi there,

I'm geting this unexpected result from a Squeak 3.9 final 7067 image.

I need to display money values with two digits. Has anybody a sugestion to correctly achieve this?

First and most important - don't maintain money as floating point numbers.

Second - never do simple compares of floating point numbers.

tim

tim Rowledge; [hidden email]; http://www.rowledge.org/tim

Strange OpCodes: FSRA: Forms Skip and Run-Away

Nicolas Cellier-3

Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29' instead of '5.30'

I can only agree and add "use ScaledDecimal".
5.3s2

Beware, Squeak::ScaledDecimal does truncate rather than round when
printing... (http://bugs.squeak.org/view.php?id=5693)
You might have to change this behavior...

Also beware of storeOn: (very minor, who is using storeOn:?).

Nicolas

tim Rowledge a écrit :

>
> On 22-Nov-07, at 10:03 AM, Sebastian Sastre wrote:
>
>> Hi there,
>>
>> I'm geting this unexpected result from a Squeak 3.9 final 7067 image.
>>
>> I need to display money values with two digits. Has anybody a
>> sugestion to correctly achieve this?
>
> First and most important - don't maintain money as floating point numbers.
> Second - never do simple compares of floating point numbers.
>
>
> tim
> --
> tim Rowledge; [hidden email]; http://www.rowledge.org/tim
> Strange OpCodes: FSRA: Forms Skip and Run-Away
>
>
>
> ------------------------------------------------------------------------
>
>

Sebastian Sastre-2

RE: 5.3 printShowingDecimalPlaces: 2 displays '5.29' instead of'5.30'

In reply to this post by timrowledge

Thanks Tim,

may be I should clarify that it's only for presentation. The mone value is stored as anMeasure of it's monetary unit in the Aconcagua framework.

But I'm curious about your answer. Let's supose the user enters in some input widget with keyboard the '5.30' value. That will end as a Float at some point. Do you suggest I convert that to a ScaledDecimal? (to store/comare, etc)?

I'm evaluating this:

(5.3 asScaledDecimal: 2)

and also obtainig: ' 5.29s2'

so I'm still lost about it,

thanks,

Sebastian Sastre

De: [hidden email] [mailto:[hidden email]] En nombre de tim Rowledge
Enviado el: Jueves, 22 de Noviembre de 2007 16:18
Para: The general-purpose Squeak developers list
Asunto: Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29' instead of'5.30'

On 22-Nov-07, at 10:03 AM, Sebastian Sastre wrote:

Hi there,

I'm geting this unexpected result from a Squeak 3.9 final 7067 image.

I need to display money values with two digits. Has anybody a sugestion to correctly achieve this?

First and most important - don't maintain money as floating point numbers.

Second - never do simple compares of floating point numbers.

tim

--

tim Rowledge; [hidden email]; http://www.rowledge.org/tim

Strange OpCodes: FSRA: Forms Skip and Run-Away

timrowledge

Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29' instead of'5.30'

On 22-Nov-07, at 11:00 AM, Sebastian Sastre wrote:

Thanks Tim,



    may be I should clarify that it's only for presentation. The mone value is stored as anMeasure of it's monetary unit in the Aconcagua framework.

    But I'm curious about your answer. Let's supose the user enters in some input widget with keyboard the '5.30' value. That will end as a Float at some point. Do you suggest I convert that to a ScaledDecimal? (to store/comare, etc)?

    I'm evaluating this:

(5.3 asScaledDecimal: 2)

    and also obtainig: ' 5.29s2'

That must surely count as a bug and I'd hazard a guess that it happens because some code is comparing floats; I've not looked at the code but I've seen it too many times not to suspect it.

As for your input widget, I'd try to make it give you the string and directly convert that to a 2dp scaled decimal rather than letting it give you a float. If there isn't a String>asScaledFloat: type method then I guess you get to write it :-)

tim

tim Rowledge; [hidden email]; http://www.rowledge.org/tim

All the simple programs have been written, and all the good names taken.

Tom Phoenix

Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29' instead of'5.30'

In reply to this post by Sebastian Sastre-2

On 11/22/07, Sebastian Sastre <[hidden email]> wrote:

> Let's supose the user enters in some
> input widget with keyboard the '5.30' value. That will end as a Float at
> some point.

Why will it?

We're talking about monetary units. If you start with a string like
'5.30', meaning 530 monetary units, it won't "end as a Float" all by
itself. If somebody somewhere wrote code that converted it to floating
point, that's a bug.

Don't be misled by what looks like a decimal point. If you're working
with money, you don't want floating point, no matter what your
programming language. Floating point will lose tiny bits due to
roundoff; but money numbers are almost always integral numbers of
cents, and you don't want to lose any of them. Floating point may be
needed to perform some calculations along the way, but you'll use
integers to get the books to balance.

ObSqueak: 5.30 asFraction

Cheers!

--Tom Phoenix

Nicolas Cellier-3

Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29' instead of'5.30'

Tome is right. Don't use a Float

In Smalltalk, use 5.30s2.

5.3 machine representation is not 53/10 though it looks like, and though
major Smalltalk dialects will answer true to 53/10=5.3 (i think they
should not - see http://bugs.squeak.org/view.php?id=3374 and
http://www.lispworks.com/documentation/lcl50/aug/aug-170.html).

You can check it with 5.3 asTrueFraction, that is
(2r10101001100110011001100110011001100110011001100110011/2r100000000000000000000000000000000000000000000000000).

And if it prints 5.29s2, then it is because of
http://bugs.squeak.org/view.php?id=5693 that you did not care to read.

* 5.3 asTrueFraction < (53/10)
* ScaledDecimal use truncated print,
=> you have the explanation.

The only thing you should try if you cannot get read of Float because of
3rd party code is:

(5.3 asScaledDecimal: 2) roundTo: 0.01s2.

Nicolas

Tom Phoenix a écrit :

> On 11/22/07, Sebastian Sastre <[hidden email]> wrote:
>
>> Let's supose the user enters in some
>> input widget with keyboard the '5.30' value. That will end as a Float at
>> some point.
>
> Why will it?
>
> We're talking about monetary units. If you start with a string like
> '5.30', meaning 530 monetary units, it won't "end as a Float" all by
> itself. If somebody somewhere wrote code that converted it to floating
> point, that's a bug.
>
> Don't be misled by what looks like a decimal point. If you're working
> with money, you don't want floating point, no matter what your
> programming language. Floating point will lose tiny bits due to
> roundoff; but money numbers are almost always integral numbers of
> cents, and you don't want to lose any of them. Floating point may be
> needed to perform some calculations along the way, but you'll use
> integers to get the books to balance.
>
> ObSqueak: 5.30 asFraction
>
> Cheers!
>
> --Tom Phoenix
>
>

Nicolas Cellier-3

Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29' instead of'5.30'

nicolas cellier a écrit :
> The only thing you should try if you cannot get read of Float because of
> 3rd party code is:

Hem, get rid...

>
> (5.3 asScaledDecimal: 2) roundTo: 0.01s2.
>

or simply:

5.3 roundTo: 0.01s2

Sebastian Sastre-2

RE: 5.3 printShowingDecimalPlaces: 2 displays '5.29' insteadof'5.30'

In reply to this post by timrowledge

Ok, don't beat me.. I'm not proud of this but I have to use until I manage to have something better.

String>>asScaledDecimal: aQuantityOfDigits
"Answers the scaled decimal with aQuantityOfDigits
of precision represented by the receiver."

^ [:number|
  number isZero
   ifTrue:[0 asFloat asScaledDecimal: aQuantityOfDigits]
   ifFalse:[number asScaledDecimal: aQuantityOfDigits]] value: self asNumber

so my converter can do this depending on it's own configuration (not only used for money):

MVPNumberToText>>rightToLeft: aString
"Answers the result of converting aString to a Number or aScaledDecimal."

^self hasInputDigits
ifTrue:[aString asScaledDecimal: inputDigits]
ifFalse:[aString asNumber]

Adding the horrible hack:

ScaledDecimal>>printOn: aStream
"Reimplementation - Object 'printing' method."
| aFraction tmpFractionPart |
self < 0 ifTrue: [aStream nextPut: $-].
aFraction := fraction abs.
aStream nextPutAll: aFraction rounded printString.
scale = 0 ifTrue: [^ aStream nextPutAll: 's0'].
aStream nextPut: $..
tmpFractionPart := aFraction fractionPart.
1 to: scale
  do:
   [:dummy |
   tmpFractionPart := tmpFractionPart * 10.
   (10 <= tmpFractionPart rounded)
    ifTrue:[aStream nextPut: $0]
    ifFalse:[aStream nextPut: (Character digitValue: tmpFractionPart rounded)].
   tmpFractionPart := tmpFractionPart fractionPart].

I was able to make the values to behave,

thanks,

Sebastian Sastre

De: [hidden email] [mailto:[hidden email]] En nombre de tim Rowledge
Enviado el: Jueves, 22 de Noviembre de 2007 17:10
Para: The general-purpose Squeak developers list
Asunto: Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29' insteadof'5.30'

On 22-Nov-07, at 11:00 AM, Sebastian Sastre wrote:

Thanks Tim,



    may be I should clarify that it's only for presentation. The mone value is stored as anMeasure of it's monetary unit in the Aconcagua framework.

    But I'm curious about your answer. Let's supose the user enters in some input widget with keyboard the '5.30' value. That will end as a Float at some point. Do you suggest I convert that to a ScaledDecimal? (to store/comare, etc)?

    I'm evaluating this:

(5.3 asScaledDecimal: 2)

    and also obtainig: ' 5.29s2'

That must surely count as a bug and I'd hazard a guess that it happens because some code is comparing floats; I've not looked at the code but I've seen it too many times not to suspect it.

As for your input widget, I'd try to make it give you the string and directly convert that to a 2dp scaled decimal rather than letting it give you a float. If there isn't a String>asScaledFloat: type method then I guess you get to write it :-)

tim

--

tim Rowledge; [hidden email]; http://www.rowledge.org/tim

All the simple programs have been written, and all the good names taken.

Bert Freudenberg

Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29' insteadof'5.30'

On Nov 22, 2007, at 21:39 , Sebastian Sastre wrote:

> Ok, don't beat me..

I promise, at least if you stop posting HTML messages to the list.

- Bert -

Sebastian Sastre-2

RE: 5.3 printShowingDecimalPlaces: 2 displays '5.29' insteadof'5.30'

In reply to this post by Tom Phoenix

> -----Mensaje original-----
> De: [hidden email]
> [mailto:[hidden email]] En
> nombre de Tom Phoenix
> Enviado el: Jueves, 22 de Noviembre de 2007 17:59
> Para: The general-purpose Squeak developers list
> Asunto: Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29'
> insteadof'5.30'
>
> On 11/22/07, Sebastian Sastre <[hidden email]> wrote:
>
> > Let's supose the user enters in some
> > input widget with keyboard the '5.30' value. That will end
> as a Float
> > at some point.
>
> Why will it?
>
> We're talking about monetary units. If you start with a
> string like '5.30', meaning 530 monetary units, it won't "end
> as a Float" all by itself. If somebody somewhere wrote code
> that converted it to floating point, that's a bug.
>

Even if you don't use computers to achieve that, when you make monetary
values to pass trhough functions they *are* mathematically represented as
float numeric values. At some point we simplify presentations (like the
balance books you mention) of the values.
I certainly agree with you about units. In fact there are equivalence units.
100 cents are 1 dollar, 4 quarters also are equal to 1 dollar and 100 cents.

Aconcagua framework seems to deal quite well with that trough it's Measures
(and amount and a unit). For monetary measures I think I'll store scaled
decimal amounts to gain the accuracy you propose.

> Don't be misled by what looks like a decimal point. If you're
> working with money, you don't want floating point, no matter
> what your programming language. Floating point will lose tiny
> bits due to roundoff; but money numbers are almost always
> integral numbers of cents, and you don't want to lose any of
> them. Floating point may be needed to perform some
> calculations along the way, but you'll use integers to get
> the books to balance.
>
I agree. With measures I think I'll be able to achieve that, by using scaled
decimanls in the amounts of the measures, and the rounding will be performed
only in presentation time by the converter of the widget and not in the
internal process, formulas or calculation of the value.

Cheers!

Sebastian

> ObSqueak: 5.30 asFraction
>
> Cheers!
>
> --Tom Phoenix
>

Nicolas Cellier-3

Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29' insteadof'5.30'

In reply to this post by Sebastian Sastre-2

Sebastian Sastre a écrit :

> Ok, don't beat me.. I'm not proud of this but I have to use until I
> manage to have something better.
>
> String>>asScaledDecimal: aQuantityOfDigits
> "Answers the scaled decimal with aQuantityOfDigits
> of precision represented by the receiver."
>
> ^ [:number|
> number isZero
> ifTrue:[0 asFloat asScaledDecimal: aQuantityOfDigits]
> ifFalse:[number asScaledDecimal: aQuantityOfDigits]] value: self
> asNumber
>

Yes, it should be (ScaledDecimal readFrom: self), but this one would
anwer a Float...

> so my converter can do this depending on it's own configuration (not
> only used for money):
>
> MVPNumberToText>>rightToLeft: aString
> "Answers the result of converting aString to a Number or aScaledDecimal."
>
> ^self hasInputDigits
> ifTrue:[aString asScaledDecimal: inputDigits]
> ifFalse:[aString asNumber]
>
> Adding the horrible hack:
>
> ScaledDecimal>>printOn: aStream
> "Reimplementation - Object 'printing' method."
> | aFraction tmpFractionPart |
> self < 0 ifTrue: [aStream nextPut: $-].
> aFraction := fraction abs.
> aStream nextPutAll: aFraction rounded printString.
> scale = 0 ifTrue: [^ aStream nextPutAll: 's0'].
> aStream nextPut: $..
> tmpFractionPart := aFraction fractionPart.
> 1 to: scale
> do:
> [:dummy |
> tmpFractionPart := tmpFractionPart * 10.
> (10 <= tmpFractionPart rounded)
> ifTrue:[aStream nextPut: $0]
> ifFalse:[aStream nextPut: (Character digitValue: tmpFractionPart
> rounded)].
> tmpFractionPart := tmpFractionPart fractionPart].
>
> I was able to make the values to behave,
>
> thanks,
>
>
> Sebastian Sastre
>
>
>
>
> ------------------------------------------------------------------------
> *De:* [hidden email]
> [mailto:[hidden email]] *En nombre de
> *tim Rowledge
> *Enviado el:* Jueves, 22 de Noviembre de 2007 17:10
> *Para:* The general-purpose Squeak developers list
> *Asunto:* Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29'
> insteadof'5.30'
>
>
> On 22-Nov-07, at 11:00 AM, Sebastian Sastre wrote:
>
>> Thanks Tim,
>>
>> may be I should clarify that it's only for presentation. The
>> mone value is stored as anMeasure of it's monetary unit in the
>> Aconcagua framework.
>>
>> But I'm curious about your answer. Let's supose the user
>> enters in some input widget with keyboard the '5.30' value. That
>> will end as a Float at some point. Do you suggest I convert that
>> to a ScaledDecimal? (to store/comare, etc)?
>>
>> I'm evaluating this:
>>
>> (5.3 asScaledDecimal: 2)
>> and also obtainig: ' 5.29s2'
>
> That must surely count as a bug and I'd hazard a guess that it
> happens because some code is comparing floats; I've not looked at
> the code but I've seen it too many times not to suspect it.
>
> As for your input widget, I'd try to make it give you the string and
> directly convert that to a 2dp scaled decimal rather than letting it
> give you a float. If there isn't a String>asScaledFloat: type method
> then I guess you get to write it :-)
>
>
> tim
> --
> tim Rowledge; [hidden email]; http://www.rowledge.org/tim
> All the simple programs have been written, and all the good names taken.
>
>
>
> ------------------------------------------------------------------------
>
>

Sebastian Sastre-2

RE: 5.3 printShowingDecimalPlaces: 2 displays '5.29' insteadof'5.30'

In reply to this post by Nicolas Cellier-3

> And if it prints 5.29s2, then it is because of
> http://bugs.squeak.org/view.php?id=5693 that you did not care to read.
>
Hey! I was reading that. That's why I'm now converting values to scaled
decimals without even passing the string representation entered in the
widget to number conversion through floats!

> * 5.3 asTrueFraction < (53/10)
> * ScaledDecimal use truncated print,
> => you have the explanation.
>
> The only thing you should try if you cannot get read of Float
> because of 3rd party code is:
>
> (5.3 asScaledDecimal: 2) roundTo: 0.01s2.
>
> Nicolas
>

Thanks for helping so accurately,

Sebastian

Sebastian Sastre-2

RE: 5.3 printShowingDecimalPlaces: 2 displays '5.29' insteadof'5.30'

In reply to this post by Bert Freudenberg

Hey I didn't know that was causing annoyances. Users should be informed
somehow.

Switching to plain text now...

Sebastian Sastre

> -----Mensaje original-----
> De: [hidden email]
> [mailto:[hidden email]] En
> nombre de Bert Freudenberg
> Enviado el: Jueves, 22 de Noviembre de 2007 18:42
> Para: The general-purpose Squeak developers list
> Asunto: Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29'
> insteadof'5.30'
>
> On Nov 22, 2007, at 21:39 , Sebastian Sastre wrote:
>
> > Ok, don't beat me..
>
> I promise, at least if you stop posting HTML messages to the list.
>
> - Bert -
>
>
>

Nicolas Cellier-3

Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29' insteadof'5.30'

In reply to this post by Sebastian Sastre-2

You're welcome,
and to push library polishing and consistency further, I propose that
(ScaledDecimal readFrom: '5.30') behave as you expect.
Try patch at http://bugs.squeak.org/view.php?id=6779

Nicolas

Sebastian Sastre a écrit :

>> And if it prints 5.29s2, then it is because of
>> http://bugs.squeak.org/view.php?id=5693 that you did not care to read.
>>
> Hey! I was reading that. That's why I'm now converting values to scaled
> decimals without even passing the string representation entered in the
> widget to number conversion through floats!
>
>> * 5.3 asTrueFraction < (53/10)
>> * ScaledDecimal use truncated print,
>> => you have the explanation.
>>
>> The only thing you should try if you cannot get read of Float
>> because of 3rd party code is:
>>
>> (5.3 asScaledDecimal: 2) roundTo: 0.01s2.
>>
>> Nicolas
>>
>
> Thanks for helping so accurately,
>
> Sebastian
>
>
>

hernan.wilkinson

Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29' insteadof'5.30'

In reply to this post by Sebastian Sastre-2

just a kick comment.
We use Fraction, no ScaledDecimal, no Float. We made some changes to fraction to work faster. We didn't see big performance diferences with ScaledDecimal.
We use measures to represent all type of quantities of some financial instrument. For example:
100 dollars
100 IBM
100 bond (any bond)
etc.

Bye,
Hernan.

On Nov 22, 2007 5:50 PM, Sebastian Sastre <[hidden email] > wrote:

> -----Mensaje original-----
> De: [hidden email]
> [mailto:[hidden email]] En
> nombre de Tom Phoenix
> Enviado el: Jueves, 22 de Noviembre de 2007 17:59
> Para: The general-purpose Squeak developers list
> Asunto: Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29'
> insteadof' 5.30'
>
> On 11/22/07, Sebastian Sastre <[hidden email]> wrote:

>
> > Let's supose the user enters in some
> > input widget with keyboard the '5.30' value. That will end
> as a Float
> > at some point.
>
> Why will it?
>
> We're talking about monetary units. If you start with a
> string like '5.30', meaning 530 monetary units, it won't "end
> as a Float" all by itself. If somebody somewhere wrote code
> that converted it to floating point, that's a bug.
>
Even if you don't use computers to achieve that, when you make monetary
values to pass trhough functions they *are* mathematically represented as
float numeric values. At some point we simplify presentations (like the
balance books you mention) of the values.
I certainly agree with you about units. In fact there are equivalence units.
100 cents are 1 dollar, 4 quarters also are equal to 1 dollar and 100 cents.

Aconcagua framework seems to deal quite well with that trough it's Measures
(and amount and a unit). For monetary measures I think I'll store scaled
decimal amounts to gain the accuracy you propose.

> Don't be misled by what looks like a decimal point. If you're
> working with money, you don't want floating point, no matter
> what your programming language. Floating point will lose tiny
> bits due to roundoff; but money numbers are almost always
> integral numbers of cents, and you don't want to lose any of
> them. Floating point may be needed to perform some
> calculations along the way, but you'll use integers to get
> the books to balance.
>
I agree. With measures I think I'll be able to achieve that, by using scaled
decimanls in the amounts of the measures, and the rounding will be performed
only in presentation time by the converter of the widget and not in the
internal process, formulas or calculation of the value.

Cheers!

Sebastian

> ObSqueak: 5.30 asFraction
>
> Cheers!
>
> --Tom Phoenix
>

Sebastian Sastre-2

RE: 5.3 printShowingDecimalPlaces: 2 displays '5.29' insteadof'5.30'

In reply to this post by Nicolas Cellier-3

Besides that, I think that #printShowingDecimalPlaces: needs a serius fix.
Evaluating for this float:

302.46 printShowingDecimalPlaces: 2

Result displaying it is '302.45'

We calculate quite well by using fractions and scaled decimals but we also
need good text representations of those fine values.

Any known patch for that?

thanks,

Sebastian Sastre

> -----Mensaje original-----
> De: [hidden email]
> [mailto:[hidden email]] En
> nombre de nicolas cellier
> Enviado el: Jueves, 22 de Noviembre de 2007 19:52
> Para: [hidden email]
> Asunto: Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29'
> insteadof'5.30'
>
> You're welcome,
> and to push library polishing and consistency further, I
> propose that (ScaledDecimal readFrom: '5.30') behave as you expect.
> Try patch at http://bugs.squeak.org/view.php?id=6779
>
> Nicolas
>
> Sebastian Sastre a écrit :
> >> And if it prints 5.29s2, then it is because of
> >> http://bugs.squeak.org/view.php?id=5693 that you did not
> care to read.
> >>
> > Hey! I was reading that. That's why I'm now converting values to
> > scaled decimals without even passing the string
> representation entered
> > in the widget to number conversion through floats!
> >
> >> * 5.3 asTrueFraction < (53/10)
> >> * ScaledDecimal use truncated print,
> >> => you have the explanation.
> >>
> >> The only thing you should try if you cannot get read of
> Float because
> >> of 3rd party code is:
> >>
> >> (5.3 asScaledDecimal: 2) roundTo: 0.01s2.
> >>
> >> Nicolas
> >>
> >
> > Thanks for helping so accurately,
> >
> > Sebastian
> >
> >
> >
>
>

Nicolas Cellier-3

Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29' insteadof'5.30'

In reply to this post by hernan.wilkinson

Hernan Wilkinson a écrit :

> just a kick comment.
> We use Fraction, no ScaledDecimal, no Float. We made some changes to
> fraction to work faster. We didn't see big performance diferences with
> ScaledDecimal.
> We use measures to represent all type of quantities of some financial
> instrument. For example:
> 100 dollars
> 100 IBM
> 100 bond (any bond)
> etc.
>
> Bye,
> Hernan.
>

You must be right.

ScaledDecimal are just fractions wrapper with special methods to read
and print...

...that do not necessarily match your required monetary format (thousand
separator, localized decimal point, no awfull s2 like in 5.30s2, append
or prepend monetary symbol etc...).

So you inevitably end up with a monetary object having its own
read/print methods, and ScaledDecimal is not of much help then...

If your Fraction optimisations are significative, please share on Mantis
or something.

Cheers

Nicolas

Nicolas Cellier-3

Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29' insteadof'5.30'

In reply to this post by Sebastian Sastre-2

Obviously, this method is weak!

Main thing is to check mantis http://bugs.squeak.org/
If not reported, please open a bug report.

If you have time, create a SUnit TestCase, file it out and upload test
on bug report.

Even better, create and upload a patch.

This time, it is already there http://bugs.squeak.org/view.php?id=5640

If the patch rocks, you review it carefully, and propose it as candidate
for image integration at http://wiki.squeak.org/squeak/5934

Cheers

Sebastian Sastre a écrit :

> Besides that, I think that #printShowingDecimalPlaces: needs a serius fix.
> Evaluating for this float:
>
> 302.46 printShowingDecimalPlaces: 2
>
> Result displaying it is '302.45'
>
> We calculate quite well by using fractions and scaled decimals but we also
> need good text representations of those fine values.
>
> Any known patch for that?
>
> thanks,
>
> Sebastian Sastre
>
>
>> -----Mensaje original-----
>> De: [hidden email]
>> [mailto:[hidden email]] En
>> nombre de nicolas cellier
>> Enviado el: Jueves, 22 de Noviembre de 2007 19:52
>> Para: [hidden email]
>> Asunto: Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29'
>> insteadof'5.30'
>>
>> You're welcome,
>> and to push library polishing and consistency further, I
>> propose that (ScaledDecimal readFrom: '5.30') behave as you expect.
>> Try patch at http://bugs.squeak.org/view.php?id=6779
>>
>> Nicolas
>>
>> Sebastian Sastre a écrit :
>>>> And if it prints 5.29s2, then it is because of
>>>> http://bugs.squeak.org/view.php?id=5693 that you did not
>> care to read.
>>> Hey! I was reading that. That's why I'm now converting values to
>>> scaled decimals without even passing the string
>> representation entered
>>> in the widget to number conversion through floats!
>>>
>>>> * 5.3 asTrueFraction < (53/10)
>>>> * ScaledDecimal use truncated print,
>>>> => you have the explanation.
>>>>
>>>> The only thing you should try if you cannot get read of
>> Float because
>>>> of 3rd party code is:
>>>>
>>>> (5.3 asScaledDecimal: 2) roundTo: 0.01s2.
>>>>
>>>> Nicolas
>>>>
>>> Thanks for helping so accurately,
>>>
>>> Sebastian
>>>
>>>
>>>
>>
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