datatype{.0 1j1
complex
On Fri, Nov 22, 2019, 10:29 AM Skip Cave <[email protected]> wrote:
> datatype >.1j0 1j1
>
> complex
>
> datatype 1j0 1j0
>
> integer
>
>
> Why not just always store 1j0 internally as a complex type? 1j1 gets stored
> as compex.
> Skip Cave
> Cave Consulting LLC
>
>
> On Fri, Nov 22, 2019 at 10:58 AM Raul Miller <[email protected]>
> wrote:
>
> > (1 j.0) would be one way of writing a constant that produces a complex
> > precision with imaginary part 0.
> >
> > Thanks,
> >
> > --
> > Raul
> >
> > On Fri, Nov 22, 2019 at 5:20 AM Henry Rich <[email protected]> wrote:
> > >
> > > 1/ Because the decoration comes before the value, it was easier to put
> > > the 0 at the beginning of the display. That's a weak argument, but
> > > that's why I did it that way.
> > >
> > > 2/ I was just thinking about this last night. You're right, for
> > > consistency complex values should be decorated. But the point of the
> > > decoration is to have a linear form that faithfully reproduces the
> > > value. 1j0 does not produce a complex value. Before the decoration,
> we
> > > need to agree on a way to write a constant that produces a complex
> > > precision with imaginary part 0.
> > >
> > > 3/ I defer to Bill on this.
> > >
> > > Henry Rich
> > >
> > > On 11/22/2019 1:04 AM, Kirk Iverson wrote:
> > > > A recent thread in the programming forum (00 strange?) inspired me to
> > look at this new behaviour in 901.
> > > >
> > > > NB. Numeric
> > > > datatype&.> 'b i f x c'=. 0 1;(0 1+0);(0 1%1);0 1x;0,1j1-0j1
> > > > +-------+-------+--------+--------+-------+
> > > > |boolean|integer|floating|extended|complex|
> > > > +-------+-------+--------+--------+-------+
> > > > b&+
> > > > 0 1&+
> > > > i&+
> > > > 00 1&+ <== (1)
> > > > f&+
> > > > 0 1.&+
> > > > x&+
> > > > 0 1x&+
> > > > c&+
> > > > 0 1&+ <== (2)
> > > >
> > > >
> > > > NB. Character
> > > > d=. (0{a.);'abc'
> > > > 'lctrl lascii'=. d
> > > > 'uctrl uascii'=. u:&.> d
> > > > 'Uctrl Uascii'=. 10 u:&.> d
> > > > datatype&.>lctrl;lascii;uctrl;uascii;Uctrl;Uascii
> > > > +-------+-------+-------+-------+--------+--------+
> > > > |literal|literal|unicode|unicode|unicode4|unicode4|
> > > > +-------+-------+-------+-------+--------+--------+
> > > > lctrl&,
> > > > (00{a.)&,
> > > > lascii&,
> > > > 'abc'&,
> > > > uctrl&,
> > > > (u: 00)&,
> > > > uascii&,
> > > > (u: 97 98 99)&, <== (3)
> > > > Uctrl&,
> > > > (10&u: 00)&,
> > > > Uascii&,
> > > > (10&u: 97 98 99)&, <== (3)
> > > >
> > > >
> > > > 1/ Is there a reason that it is the first element of an integer array
> > which has extra decoration, rather than the last element (as in the other
> > cases)?
> > > >
> > > > 2/ Shouldn't this display as 0 1j0&+ ?
> > > > Also, when interpreting constants in a line of J:
> > > > 0 1 is boolean
> > > > 00 1 is integer
> > > > 0 1. is floating
> > > > 0 1x is extended (as is 0 1r1)
> > > > 0 1j0 is integer
> > > > Shouldn't this last one be complex?
> > > >
> > > > 3/ Can the representations of uascii and Uascii make use of literals
> > (like lascii does)?
> > > >
> > > > /K
> > > >
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