Decimal.Round lunacy

[Rob Oldfield]

From the documentation about Decimal.Round.. ..

"When d is exactly halfway between two rounded values, the result is the
rounded value that has an even digit in the far right decimal position. For
example, when rounded to two decimals, the value 2.345 becomes 2.34 and the
value 2.355 becomes 2.36. This process is known as rounding toward even, or
rounding to nearest."

I'd have to disagree. I'd go for something more like "This process is known
is arbitrarily ignoring a de facto standard." Does anyone have a sensible
method of returning the correct rounded value i.e. without resorting to
decimal.round(x +0.00000001,2)

And has anyone got any justification for this ludicrousness?

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[NoOne]

This is actually pretty standard. Do a search on google for papers and
such....

"Rob Oldfield" <r$ob@oldfi$eld 100.freese$rve. c$o.uk> wrote in message
news:OD******** ******@TK2MSFTN GP12.phx.gbl...

From the documentation about Decimal.Round.. ..

"When d is exactly halfway between two rounded values, the result is the
rounded value that has an even digit in the far right decimal position. For example, when rounded to two decimals, the value 2.345 becomes 2.34 and the value 2.355 becomes 2.36. This process is known as rounding toward even, or rounding to nearest."

I'd have to disagree. I'd go for something more like "This process is known is arbitrarily ignoring a de facto standard." Does anyone have a sensible
method of returning the correct rounded value i.e. without resorting to
decimal.round(x +0.00000001,2)

And has anyone got any justification for this ludicrousness?

--
For real reply address, lose the cash
www.realuk.co.uk

[NoOne]

Ooops.. Its called Banker's rounding
"NoOne" <[e-mail] > wrote in message
news:eN******** *****@TK2MSFTNG P09.phx.gbl...

This is actually pretty standard. Do a search on google for papers and
such....

"Rob Oldfield" <r$ob@oldfi$eld 100.freese$rve. c$o.uk> wrote in message
news:OD******** ******@TK2MSFTN GP12.phx.gbl...

From the documentation about Decimal.Round.. ..

"When d is exactly halfway between two rounded values, the result is the
rounded value that has an even digit in the far right decimal position.

For

example, when rounded to two decimals, the value 2.345 becomes 2.34 and

the

value 2.355 becomes 2.36. This process is known as rounding toward even,

or

rounding to nearest."

I'd have to disagree. I'd go for something more like "This process is

known

is arbitrarily ignoring a de facto standard." Does anyone have a sensible method of returning the correct rounded value i.e. without resorting to
decimal.round(x +0.00000001,2)

And has anyone got any justification for this ludicrousness?

--
For real reply address, lose the cash
www.realuk.co.uk

[Rob Oldfield]

I repeat. It's lunacy. It might be a good idea, but the fact is that
NOBODY ACTUALLY DOES IT THIS WAY.

Well, that might be an exaggeration, but very few people.

--
For real reply address, lose the cash
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"NoOne" <[e-mail] > wrote in message
news:#k******** ******@TK2MSFTN GP10.phx.gbl...

Ooops.. Its called Banker's rounding
"NoOne" <[e-mail] > wrote in message
news:eN******** *****@TK2MSFTNG P09.phx.gbl...

This is actually pretty standard. Do a search on google for papers and
such....

"Rob Oldfield" <r$ob@oldfi$eld 100.freese$rve. c$o.uk> wrote in message
news:OD******** ******@TK2MSFTN GP12.phx.gbl...

From the documentation about Decimal.Round.. ..

"When d is exactly halfway between two rounded values, the result is the rounded value that has an even digit in the far right decimal position.

For

example, when rounded to two decimals, the value 2.345 becomes 2.34

and

the

value 2.355 becomes 2.36. This process is known as rounding toward

even, or

rounding to nearest."

I'd have to disagree. I'd go for something more like "This process is

known

is arbitrarily ignoring a de facto standard." Does anyone have a

sensible method of returning the correct rounded value i.e. without resorting

to decimal.round(x +0.00000001,2)

And has anyone got any justification for this ludicrousness?

--
For real reply address, lose the cash
www.realuk.co.uk

[c# newbie]

write your own method then.

make an enum of values ( like odd, even digits )
and make up a rule.

"Rob Oldfield" <r$ob@oldfi$eld 100.freese$rve. c$o.uk> wrote in message
news:OD******** ******@TK2MSFTN GP12.phx.gbl...

From the documentation about Decimal.Round.. ..

"When d is exactly halfway between two rounded values, the result is the
rounded value that has an even digit in the far right decimal position. For example, when rounded to two decimals, the value 2.345 becomes 2.34 and the value 2.355 becomes 2.36. This process is known as rounding toward even, or rounding to nearest."

I'd have to disagree. I'd go for something more like "This process is known is arbitrarily ignoring a de facto standard." Does anyone have a sensible
method of returning the correct rounded value i.e. without resorting to
decimal.round(x +0.00000001,2)

And has anyone got any justification for this ludicrousness?

--
For real reply address, lose the cash
www.realuk.co.uk

[Rob Oldfield]

I could do that, yes. The reason for the question is with the hope that
somebody else has already done it and would be willing to share their code.

I still say that it's ludicrous that MS didn't get it right to start off
with. Would it be OK if the '+' operator worked perfectly except on
Tuesday's. Perfectly simple to replace function add(x,y) with....

dim newY
if day=tuesday
newY=y*-1
add=x-y
else
add=x+y
end if

....but still monumentally stupid.

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"c# newbie" <no****@leave.m e.alone> wrote in message
news:31******** *************** *******@news.te ranews.com...

write your own method then.

make an enum of values ( like odd, even digits )
and make up a rule.

"Rob Oldfield" <r$ob@oldfi$eld 100.freese$rve. c$o.uk> wrote in message
news:OD******** ******@TK2MSFTN GP12.phx.gbl...

From the documentation about Decimal.Round.. ..

"When d is exactly halfway between two rounded values, the result is the
rounded value that has an even digit in the far right decimal position.

For

example, when rounded to two decimals, the value 2.345 becomes 2.34 and

the

value 2.355 becomes 2.36. This process is known as rounding toward even,

or

rounding to nearest."

I'd have to disagree. I'd go for something more like "This process is

known

is arbitrarily ignoring a de facto standard." Does anyone have a sensible method of returning the correct rounded value i.e. without resorting to
decimal.round(x +0.00000001,2)

And has anyone got any justification for this ludicrousness?

--
For real reply address, lose the cash
www.realuk.co.uk

[William Ryan]

MS has a reason for doing it, but you're not alone in your frustration, b/c
many don't realize it until after it's too late. At least an overload
should have been provided so you can use either method IMHO.
"Rob Oldfield" <r$ob@oldfi$eld 100.freese$rve. c$o.uk> wrote in message
news:OD******** ******@TK2MSFTN GP12.phx.gbl...

From the documentation about Decimal.Round.. ..

"When d is exactly halfway between two rounded values, the result is the
rounded value that has an even digit in the far right decimal position. For example, when rounded to two decimals, the value 2.345 becomes 2.34 and the value 2.355 becomes 2.36. This process is known as rounding toward even, or rounding to nearest."

I'd have to disagree. I'd go for something more like "This process is known is arbitrarily ignoring a de facto standard." Does anyone have a sensible
method of returning the correct rounded value i.e. without resorting to
decimal.round(x +0.00000001,2)

And has anyone got any justification for this ludicrousness?

--
For real reply address, lose the cash
www.realuk.co.uk

[Jon Skeet [C# MVP]]

William Ryan <do********@com cast.nospam.net > wrote:

MS has a reason for doing it, but you're not alone in your frustration, b/c
many don't realize it until after it's too late. At least an overload
should have been provided so you can use either method IMHO.

Rather than an overload, there should be an enumeration of rounding
types, or possibly something like the Encoding hierarchy.

--
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http://www.pobox.com/~skeet
If replying to the group, please do not mail me too

[Jon Skeet [C# MVP]]

Rob Oldfield <r$ob@oldfi$eld 100.freese$rve. c$o.uk> wrote:

I repeat. It's lunacy. It might be a good idea, but the fact is that
NOBODY ACTUALLY DOES IT THIS WAY.

Well, that might be an exaggeration, but very few people.

I suspect that decimal is generally intended for financial
applications, and given that the name is "banker's rounding" my guess
is that it's not uncommon in that sector. I don't personally have a lot
of experience with the financial sector - do you?

--
Jon Skeet - <sk***@pobox.co m>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too

[Rob Oldfield]

The app that I'm writing that this error has just come up is for an
investment house. When I told their accounts manager that this was the
problem his reaction was "That's absolutely ludicrous. I've never heard of
anyone doing it that way."

This is in the UK though, it may be that things are different in the US, but
certainly 'rounding' over here is 100% 'round halves upwards'.

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"Jon Skeet [C# MVP]" <sk***@pobox.co m> wrote in message
news:MP******** *************** *@msnews.micros oft.com...

Rob Oldfield <r$ob@oldfi$eld 100.freese$rve. c$o.uk> wrote:

I repeat. It's lunacy. It might be a good idea, but the fact is that
NOBODY ACTUALLY DOES IT THIS WAY.

Well, that might be an exaggeration, but very few people.

I suspect that decimal is generally intended for financial
applications, and given that the name is "banker's rounding" my guess
is that it's not uncommon in that sector. I don't personally have a lot
of experience with the financial sector - do you?

--
Jon Skeet - <sk***@pobox.co m>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too