A candidate implementation of decimal numbers (arbitrary-precision
floating-point numbers) is available for review at
https://github.com/andersonpd/eris/tree/master/eris/decimal. This is a
substantial rework of an earlier implementation which was located at
https://github.com/andersonpd/decimal.

This is a D language implementation of the General Decimal Arithmetic
Specification (http://www.speleotrove.com/decimal/decarith.pdf), which is
compliant with IEEE-754 and other standards as noted in the specification.

The current implementation is not complete; there are a lot of TODOs and NOTEs
scattered throughout the code, but all the arithmetic and miscellaneous
operations listed in the spec are working, along with decimal versions of most
of the functions and constants in std.math. I think it is far enough along for
effective review.

Briefly, this software adds the capability of properly rounded
arbitrary-precision floating-point arithmetic to the D language. All arithmetic
operations are governed by a "context", which specifies the precision (number of
decimal digits) and rounding mode for the operations. This same functionality
exists in most modern computer languages (for example, java.math.BigDecimal).
Unlike Java, however, which uses function syntax for arithmetic ops
(add(BigDecimal, BigDecimal), etc.), in D the same arithmetic operators that
work for floats or doubles work for decimal numbers. (Of course!)

In this implementation decimal numbers having different contexts are different
types. The types are specified using template parameters for the precision,
maximum exponent value and rounding mode. This means that
Decimal!(9,99,Rounding.HALF_EVEN) is a different type than
Decimal!(19,199,Rounding.HALF_DOWN). They are largely interoperable, however.
Different decimal types can be cast to and from each
other.

There are three standard decimal structs which fit into 32-, 64- and 128-bits of
memory, with 7, 16 and 34 digit precision, respectively. These are used for
compact storage; they are converted to their corresponding decimal numbers for
calculation. They bear the same relation to decimal numbers as Walter's
half-float type does to floats.
(http://www.drdobbs.com/cpp/implementing-half-floats-in-d/240146674).
Implementation of these still needs a little work, and will be added to github
very shortly.

Major TODO items:

1) The current underlying integer type uses my own big integer struct
(eris.integer.extended) rather than std.bigint. This was mainly due to problems
with constness and CTFE of BigInts. These problems have since been resolved, but
I didn't want to switch over to BigInts until everything was working for fear of
introducing new bugs.

2) Integration of Decimal32, Decimal64 and Decimal128 structs are not complete.
(See above.)

3) Conversion to and from floats, doubles and reals is currently working but it
is slow. (Conversion is through strings: double to string to decimal and vice
versa.)

4) Still incomplete implementations of some functions in decimal.math: expm1,
acosh, atanh, possibly others.

5) More unit tests (always!).

Sorry for the unusual formatting.

Paul

On 3 Jul 2014 23:00, "Paul D Anderson via Digitalmars-d-announce" < digitalmars-d-announce@puremagic.com> wrote:
>
> A candidate implementation of decimal numbers (arbitrary-precision floating-point numbers) is available for review at https://github.com/andersonpd/eris/tree/master/eris/decimal. This is a substantial rework of an earlier implementation which was located at https://github.com/andersonpd/decimal.
>
> This is a D language implementation of the General Decimal Arithmetic Specification (http://www.speleotrove.com/decimal/decarith.pdf), which is compliant with IEEE-754 and other standards as noted in the specification.
>
> The current implementation is not complete; there are a lot of TODOs and
NOTEs
> scattered throughout the code, but all the arithmetic and miscellaneous operations listed in the spec are working, along with decimal versions of
most
> of the functions and constants in std.math. I think it is far enough
along for
> effective review.
>
> Briefly, this software adds the capability of properly rounded arbitrary-precision floating-point arithmetic to the D language. All
arithmetic
> operations are governed by a "context", which specifies the precision
(number of
> decimal digits) and rounding mode for the operations. This same
functionality
> exists in most modern computer languages (for example,
java.math.BigDecimal).
> Unlike Java, however, which uses function syntax for arithmetic ops
> (add(BigDecimal, BigDecimal), etc.), in D the same arithmetic operators
that
> work for floats or doubles work for decimal numbers. (Of course!)
>
> In this implementation decimal numbers having different contexts are
different
> types. The types are specified using template parameters for the
precision,
> maximum exponent value and rounding mode. This means that
> Decimal!(9,99,Rounding.HALF_EVEN) is a different type than
> Decimal!(19,199,Rounding.HALF_DOWN). They are largely interoperable,
however.
> Different decimal types can be cast to and from each
> other.
>
> There are three standard decimal structs which fit into 32-, 64- and
128-bits of
> memory, with 7, 16 and 34 digit precision, respectively. These are used
for
> compact storage; they are converted to their corresponding decimal
numbers for
> calculation. They bear the same relation to decimal numbers as Walter's half-float type does to floats. (http://www.drdobbs.com/cpp/implementing-half-floats-in-d/240146674). Implementation of these still needs a little work, and will be added to
github
> very shortly.
>
> Major TODO items:
>
> 1) The current underlying integer type uses my own big integer struct
> (eris.integer.extended) rather than std.bigint. This was mainly due to
problems
> with constness and CTFE of BigInts. These problems have since been
resolved, but
> I didn't want to switch over to BigInts until everything was working for
fear of
> introducing new bugs.
>
> 2) Integration of Decimal32, Decimal64 and Decimal128 structs are not
complete.
> (See above.)
>
> 3) Conversion to and from floats, doubles and reals is currently working
but it
> is slow. (Conversion is through strings: double to string to decimal and
vice
> versa.)
>
> 4) Still incomplete implementations of some functions in decimal.math:
expm1,
> acosh, atanh, possibly others.
>
> 5) More unit tests (always!).

Nice job.

I would also add:

6) Rename the file decimal.d to package.d, and module eris.decimal.decimal to eris.decimal

On Friday, 4 July 2014 at 06:43:15 UTC, Iain Buclaw via Digitalmars-d-announce wrote:
>
> 6) Rename the file decimal.d to package.d, and module eris.decimal.decimal
> to eris.decimal

Thanks, will do.

Paul

On Thursday, 3 July 2014 at 21:55:42 UTC, Paul D Anderson wrote:
> A candidate implementation of decimal numbers (arbitrary-precision
> floating-point numbers) is available for review at
> https://github.com/andersonpd/eris/tree/master/eris/decimal. This is a
> substantial rework of an earlier implementation which was located at
> https://github.com/andersonpd/decimal.
>
> This is a D language implementation of the General Decimal Arithmetic
> Specification (http://www.speleotrove.com/decimal/decarith.pdf), which is
> compliant with IEEE-754 and other standards as noted in the specification.
>
> The current implementation is not complete; there are a lot of TODOs and NOTEs
> scattered throughout the code, but all the arithmetic and miscellaneous
> operations listed in the spec are working, along with decimal versions of most
> of the functions and constants in std.math. I think it is far enough along for
> effective review.
>
> Briefly, this software adds the capability of properly rounded
> arbitrary-precision floating-point arithmetic to the D language. All arithmetic
> operations are governed by a "context", which specifies the precision (number of
> decimal digits) and rounding mode for the operations. This same functionality
> exists in most modern computer languages (for example, java.math.BigDecimal).
> Unlike Java, however, which uses function syntax for arithmetic ops
> (add(BigDecimal, BigDecimal), etc.), in D the same arithmetic operators that
> work for floats or doubles work for decimal numbers. (Of course!)
>
> In this implementation decimal numbers having different contexts are different
> types. The types are specified using template parameters for the precision,
> maximum exponent value and rounding mode. This means that
> Decimal!(9,99,Rounding.HALF_EVEN) is a different type than
> Decimal!(19,199,Rounding.HALF_DOWN). They are largely interoperable, however.
> Different decimal types can be cast to and from each
> other.
>
> There are three standard decimal structs which fit into 32-, 64- and 128-bits of
> memory, with 7, 16 and 34 digit precision, respectively. These are used for
> compact storage; they are converted to their corresponding decimal numbers for
> calculation. They bear the same relation to decimal numbers as Walter's
> half-float type does to floats.
> (http://www.drdobbs.com/cpp/implementing-half-floats-in-d/240146674).
> Implementation of these still needs a little work, and will be added to github
> very shortly.
>
> Major TODO items:
>
> 1) The current underlying integer type uses my own big integer struct
> (eris.integer.extended) rather than std.bigint. This was mainly due to problems
> with constness and CTFE of BigInts. These problems have since been resolved, but
> I didn't want to switch over to BigInts until everything was working for fear of
> introducing new bugs.
>
> 2) Integration of Decimal32, Decimal64 and Decimal128 structs are not complete.
> (See above.)
>
> 3) Conversion to and from floats, doubles and reals is currently working but it
> is slow. (Conversion is through strings: double to string to decimal and vice
> versa.)
>
> 4) Still incomplete implementations of some functions in decimal.math: expm1,
> acosh, atanh, possibly others.
>
> 5) More unit tests (always!).


This is looking very promising!

On Thursday, 3 July 2014 at 21:55:42 UTC, Paul D Anderson wrote:
> A candidate implementation of decimal numbers (arbitrary-precision
> floating-point numbers) is available for review at
> https://github.com/andersonpd/eris/tree/master/eris/decimal. This is a
> substantial rework of an earlier implementation which was located at
> https://github.com/andersonpd/decimal.
>
> This is a D language implementation of the General Decimal Arithmetic
> Specification (http://www.speleotrove.com/decimal/decarith.pdf), which is
> compliant with IEEE-754 and other standards as noted in the specification.
>
> The current implementation is not complete; there are a lot of TODOs and NOTEs
> scattered throughout the code, but all the arithmetic and miscellaneous
> operations listed in the spec are working, along with decimal versions of most
> of the functions and constants in std.math. I think it is far enough along for
> effective review.
>
> Briefly, this software adds the capability of properly rounded
> arbitrary-precision floating-point arithmetic to the D language. All arithmetic
> operations are governed by a "context", which specifies the precision (number of
> decimal digits) and rounding mode for the operations. This same functionality
> exists in most modern computer languages (for example, java.math.BigDecimal).
> Unlike Java, however, which uses function syntax for arithmetic ops
> (add(BigDecimal, BigDecimal), etc.), in D the same arithmetic operators that
> work for floats or doubles work for decimal numbers. (Of course!)
>
> In this implementation decimal numbers having different contexts are different
> types. The types are specified using template parameters for the precision,
> maximum exponent value and rounding mode. This means that
> Decimal!(9,99,Rounding.HALF_EVEN) is a different type than
> Decimal!(19,199,Rounding.HALF_DOWN). They are largely interoperable, however.
> Different decimal types can be cast to and from each
> other.
>
> There are three standard decimal structs which fit into 32-, 64- and 128-bits of
> memory, with 7, 16 and 34 digit precision, respectively. These are used for
> compact storage; they are converted to their corresponding decimal numbers for
> calculation. They bear the same relation to decimal numbers as Walter's
> half-float type does to floats.
> (http://www.drdobbs.com/cpp/implementing-half-floats-in-d/240146674).
> Implementation of these still needs a little work, and will be added to github
> very shortly.
>
> Major TODO items:
>
> 1) The current underlying integer type uses my own big integer struct
> (eris.integer.extended) rather than std.bigint. This was mainly due to problems
> with constness and CTFE of BigInts. These problems have since been resolved, but
> I didn't want to switch over to BigInts until everything was working for fear of
> introducing new bugs.
>
> 2) Integration of Decimal32, Decimal64 and Decimal128 structs are not complete.
> (See above.)
>
> 3) Conversion to and from floats, doubles and reals is currently working but it
> is slow. (Conversion is through strings: double to string to decimal and vice
> versa.)
>
> 4) Still incomplete implementations of some functions in decimal.math: expm1,
> acosh, atanh, possibly others.
>
> 5) More unit tests (always!).

I have spend some times fixing this and now it compiles with DMD 2.066.
Also fixed some tests.
https://github.com/Remotion/decimal

Can you add a dub.json and submit it to the dub registry?

On Monday, 7 July 2014 at 03:26:54 UTC, Poyeyo wrote:
> Can you add a dub.json and submit it to the dub registry?

I can do that but I want to get the 32-, 64- and 128-bit structs in place first. Probably by midweek (July 9).

On Monday, 7 July 2014 at 03:26:54 UTC, Poyeyo wrote:
> Can you add a dub.json and submit it to the dub registry?

etcimon generated a dub.json file which I've merged into github. Thanks.

However, I am unable to register the package because it requires a version number, which I don't know how to add. I've used git tag and edited dub.selections.json, but neither seems to be the answer. Can someone enlighten me?

Paul

Am 07.07.2014 23:15, schrieb Paul D Anderson:
> On Monday, 7 July 2014 at 03:26:54 UTC, Poyeyo wrote:
>> Can you add a dub.json and submit it to the dub registry?
>
> etcimon generated a dub.json file which I've merged into github. Thanks.
>
> However, I am unable to register the package because it requires a
> version number, which I don't know how to add. I've used git tag and
> edited dub.selections.json, but neither seems to be the answer. Can
> someone enlighten me?
>
> Paul

git tag v0.9.0
git push --tags

should do the trick (as well as any other version instead of 0.9.0, of course).