Hi Fred,
Rational. and non-rational numbers use the same Cell type
(FloatCell).
Non-Rational numbers have a denominator = 0 and store their
value in value.fval.u1.flt (which is a double in
union u1)
Rational numbers have a denominator >= 1 and stor
Hello Jürgen,
After reading your email and the apl.html documentation on ⎕CR
and so, I've have two questions:
1) How does one know B is a rational number? The apl.html
documentation for 26 ⎕CR B does not showthat there is a cell type for
rationals and I could not locate one in the
Hi Fred,
the existing mechanism is 27 ⎕CR B to get the numerator of
B and 28 ⎕CR to get the denominator > 0
of a quotient or 0 if the number is not a quotient (and then 27
⎕CR is the double B cast to uint64_t.
Unfortunately there was a bug 28 ⎕
Guys,
To make it clear, I'm not asking for bigints. I'm just seeking
to get the maximum benefit of having rational numbers with, as Xtian
says, ~63-bit numerator and denominators. As long as you limit
yourself to using addition, subtraction, multiplication, and division
and avoid overrunn
A bigint is an arbitrary-precision integer. Such as what is provided in
Lisp:
In Lisp, I get the correct rational number:
CL> *(/ (expt 2 1000) 3)*
10715086071862673209484250490600018105614048117055336074437503883703510511249361224931983788156958581275946729175531468251871452856923140435984577574
what is "bigints" ?
larger than ~62 bits or 920 ?
If so, I would agree 100%. Having a limit that is less than exact 64 bits
(signed or unsigned)
is wrong. encode & decode can't manage more than ~62-~63 bits limit.
my 2 cents,
Xtian.
On 2017-08-28 22:33, Elias Mårtenson wrote:
The true benefit of rational numbers is realised once there is support for
bigints. Jürgen has suggested that that is planned, and personally I can't
wait.
Regards,
Elias
On 29 August 2017 at 08:59, Frederick Pitts wrote:
> Louis,
>
> Thanks for the quick response.
>
> After wor
Louis,
Thanks for the quick response.
After working with the technique a bit, I observe that as long
as the rational number denominator is well within the range of integers
representable by floating numbers, 1 ∧ n returns the correct result.
But if the absolute value of the denomi
Hi,
No APL kb with me right now, sorry :(
1 LCM n
gives the numerator of a fraction (floating or exact). If you need the
denominator, do the same with the inverse of n. If you need both, for example:
1 LCM n POW 1 _1
Cheers,
Louis
> On 28 Aug 2017, at 23:24, Frederick Pitts wrote:
>
> Hell
Hello,
Is there an existing mechanism for accessing rational number
numerator and denominator parts analogous to that for accessing complex
number real and imaginary parts? If yes, please let me know how. If
no, can a mechanism be implemented?
Respectfully,
Fred
10 matches
Mail list logo
