> showing that the argument (4) is actually a cardinal number rather
> than an ordinal number. The element (4 { i.7) is not the fourth but
> rather the first after having dropped 4 elements. The element

> dropped 0 elements. There are no ordinal numbers in J.

I  was referring to the finite mathematical ordinals, which are the same as
the finite mathematical cardinals, which are the same as the natural
numbers (0, 1, 2, ... ); thus, your comments about ordinal numbers do not
apply to them.



On Wed, May 30, 2018 at 9:08 PM, 'Bo Jacoby' via Chat <[email protected]>
wrote:

>
> The verb ({) can be considered shorthand for ([:{.}.)
> 4 { i.7
> 4
>  4 ([:{.}.) i.7
> 4
> showing that the argument (4) is actually a cardinal number rather than an
> ordinal number. The element (4 { i.7) is not the fourth but rather the
> first after having dropped 4 elements. The element (0 { i.7) is not the
> "zeroth" but rather the first after having dropped 0 elements. There are no
> ordinal numbers in J.
>
>     Den 1:54 torsdag den 31. maj 2018 skrev Jose Mario Quintana <
> [email protected]>:
>
>
>  Raul Miller:
> > This dating system dates back to the romans, and pre-dates the invention
> of
> > the zero.
>
> Right, it preceded the invention of the zero in both, the New World, and
> the Old World.
>
> Bo Jacoby:
> > Are you missing the point? The ordinal numbers used for counting
> centuries
> > and years are  1. 2. 3. and so on. No such thing as a zeroth century.
>
> I do not think so.  I am aware that there are different perspectives.
>
> There is no "zeroth century" in between the 1st century BC and the 1st
> century AD (also written just as the 1st century).  However, zeroth is
> currently regarded as a word in English and, in that sense of the word, the
> zeroth century AD is the 1st century BC and the zeroth century BC is the
> 1st century AD.  (It is a mess precisely because there is no "zeroth
> century" in between!)
>
> One of the dates I mentioned, 13.0.0.0.0, is written in the modern notation
> of the Long Count Calendar.  This date, which coincided with a winter
> solstice, refers to the day 0 (i.e., the first day in the context of the
> common English language) of a new cycle.
>
> Likewise, the finite mathematical ordinals are 0, 1, 2, ... and J seems to
> follow this scheme; see, for example,
>
> A. Nouns
>   http://www.jsoftware.com/help/dictionary/dicta.htm
>
> In particular, as I showed it before in a previous message (see below), the
> verb { selects the items of its right argument in this natural way.
> Although, if one is prepared to go backward, one can also do the following,
>
>   _2 _1{ '3rd' ; '2nd' ; '1st'
> ┌───┬───┐
> │2nd│1st│
> └───┴───┘
>   _3 { '3rd' ; '2nd' ; '1st'
> ┌───┐
> │3rd│
> └───┘
>
> PS. From my vantage point, a series of messages preceding this one
> illustrates beautifully what happens when you do not start from zero ;)
>
>
> On Wed, May 30, 2018 at 9:10 AM, Raul Miller <[email protected]>
> wrote:
>
> > Right: the year 1941 was in the twentieth century.
> >
> > This dating system dates back to the romans, and pre-dates the invention
> of
> > the zero.
> >
> > Thanks,
> >
> > —
> > Raul
> >
> > On Wednesday, May 30, 2018, 'Bo Jacoby' via Chat <[email protected]>
> > wrote:
> >
> > > Are you missing the point? The ordinal numbers used for counting
> > centuries
> > > and years are  1. 2. 3. and so on. No such thing as a zeroth century.
> > > 0-origin indexing is useful, but the numbers are not ordinal. The
> degree
> > of
> > > a polynomial is the maximum exponent, and the exponents are cardinal
> > > numbers. So "second degree" is bad language for degree 2.
> > >
> > >    Den 0:59 onsdag den 30. maj 2018 skrev Jose Mario Quintana <
> > > [email protected]>:
> > >
> > >
> > >  This nice day, May 29, 2018, according to some Day Keepers, is
> > 13.0.5.9.5.
> > > That is right, they have been counting days avoiding inevitable
> > complicated
> > > correction rules when trying to synchronize years and days (KISS).
> (Yet,
> > > the date 13.0.0.0.0 corresponded to December 21, 2012.)
> > >
> > >
> > > On Tue, May 29, 2018 at 9:16 AM, Raul Miller <[email protected]>
> > > wrote:
> > >
> > > > Clearly, this year is 10 Prairial CCXXVI
> > > >
> > > > Well, unless you are using the Hebrew calendar - then it’s the year
> > 5778.
> > > >
> > > > Etc...
> > > >
> > > > (Translation: the answer here depends on your religious beliefs)
> > > >
> > > > I hope this helps.
> > > >
> > > > Have a nice day.
> > > >
> > > > Thanks,
> > > >
> > > > —
> > > > Raul
> > > >
> > > > On Tuesday, May 29, 2018, 'Bo Jacoby' via Chat <[email protected]>
> > > wrote:
> > > >
> > > > > Do we agree that this year, AD 2018, is the eighth year of the of
> the
> > > > > second decade of the first century of the third millenium? Or do
> you
> > > > > consider it to be the seventh year of the first decade of the
> zeroth
> > > > > century of the second millenium? The time passed until year 2018
> are
> > 2
> > > > > millenia, 0 centuries, 1 decade and 7 years, but those are not
> > ordinal
> > > > > numbers.
> > > > >
> > > > >    Den 3:41 tirsdag den 29. maj 2018 skrev Jose Mario Quintana <
> > > > > [email protected]>:
> > > > >
> > > > >
> > > > >  Personally, I feel more comfortable with the usual mathematical
> > > > > perspective: 0 is the first ordinal, 1 is the second, etc.
> Moreover,
> > > > from
> > > > > this perspective (as far as I remember), there is no difference
> > between
> > > > > finite cardinal and ordinal numbers.
> > > > >
> > > > >  ] A=. 'First' ; 'Second' ; 'Third' ; 'Fourth' ; 'Fifth'
> > > > > ┌─────┬──────┬─────┬──────┬─────┐
> > > > > │First│Second│Third│Fourth│Fifth│
> > > > > └─────┴──────┴─────┴──────┴─────┘
> > > > >  0 { A
> > > > > ┌─────┐
> > > > > │First│
> > > > > └─────┘
> > > > >  1 2 3 4 { A
> > > > > ┌──────┬─────┬──────┬─────┐
> > > > > │Second│Third│Fourth│Fifth│
> > > > > └──────┴─────┴──────┴─────┘
> > > > >
> > > > >
> > > > > On Sat, May 26, 2018 at 12:38 AM, 'Bo Jacoby' via Chat <
> > > > [email protected]
> > > > > >
> > > > > wrote:
> > > > >
> > > > > > Ordinal numbers are not considered in J. The expression 2{y
> should
> > > not
> > > > be
> > > > > > read as "take the second element of y" but as "skip 2 elements
> and
> > > take
> > > > > the
> > > > > > left element of y".
> > > > > > Ordinal Fractions use one-digit ordinal numbers for indexing.
> There
> > > are
> > > > > > but nine one-digit ordinal numbers: 1 2 3 4 5 6 7 8 9, because 0
> is
> > > not
> > > > > an
> > > > > > ordinal number, and 10 is not a one-digit number. Digit 0 - not
> > being
> > > > an
> > > > > > ordinal number - is available to indicate empty digit positions.
> > > > > >
> > > > > > Example: The roman numeral MMLIII means (M*2)+(L*1)+(I*3) . It
> can
> > be
> > > > > > encoded (arabic style) without delimiting spaces: 2001003 . The
> > > zeroes
> > > > > > in 2001003 mean that terms involving D C X and V are omitted.
> > > Likewise,
> > > > > the
> > > > > > ordinal fraction 2001003 means (M=2)*.(L=1)*.(I=3). The zeroes
> > > > > > in 2001003 mean that conditions involving D C X and V are
> omitted.
> > > > > > Thanks.
> > > > > > Bo.
> > > > > >    Den 0:06 lørdag den 26. maj 2018 skrev Jose Mario Quintana <
> > > > > > [email protected]>:
> > > > > >
> > > > > >
> > > > > >  Stopwatches and odometers can also be used to label time
> intervals
> > > to
> > > > > > associate them to events occurring in those intervals and keep
> > track
> > > of
> > > > > the
> > > > > > order in which they take place.  In fact, conceptual odometers
> > > counting
> > > > > > days have been used at least for two millennia and detecting a
> day
> > > > when a
> > > > > > big cycle ends and the day when the next begins is extremely hard
> > to
> > > > > miss.
> > > > > >
> > > > > > In addition, by starting at 0 when labelling sequential objects
> the
> > > > > offset
> > > > > > from the anchor is immediately evident; for instance, if the
> > buttons
> > > in
> > > > > an
> > > > > > elevator for the floors of the building are labelled: *G (0), 1
> ,2,
> > > ...
> > > > > and
> > > > > > I pressed 6, to get to the floor where I am then I know that if a
> > > fire
> > > > > > alarm goes off I will go down the stairs 6 floors and I will be
> on
> > > the
> > > > > > ground floor.  However, if the fire alarm would go off right now
> in
> > > my
> > > > > > building, ... I would do nothing because there are too many damn
> > > false
> > > > > > alarms!
> > > > > >
> > > > > > In the context of the common English language, there is little
> > doubt
> > > > that
> > > > > > the ordinal numbers are 1st, 2nd, 3rd, 4th, ...  However, in
> > another
> > > > > > context (see, https://en.wikipedia.org/wiki/Ordinal_number )
> they
> > > are
> > > > 0,
> > > > > > 1,
> > > > > > 2, ... (, ω, and so on).
> > > > > >
> > > > > > Personally, I have no problem relating both by saying 0 is the
> 1st
> > > > > ordinal
> > > > > > number, 1 is the 2nd ordinal, 2 is the 3rd ordinal, 3 is the 4th
> > > > ordinal,
> > > > > > etc.
> > > > > >
> > > > > > I understand that there could be instances where starting from 1
> > > might
> > > > be
> > > > > > more desirable; apparently, that is the case for your Ordinal
> > > Fractions
> > > > > > where the digit 0 is used for a special purpose (although I
> cannot
> > > see
> > > > > the
> > > > > > difficulty in starting from 0 and using, say, _ for the special
> > > > purpose).
> > > > > >
> > > > > >
> > > > > > On Fri, May 25, 2018 at 5:52 PM, Jose Mario Quintana <
> > > > > > [email protected]> wrote:
> > > > > >
> > > > > > > :D
> > > > > > >
> > > > > > > It seems that these people like complications.  They are not
> very
> > > > smart
> > > > > > or
> > > > > > > maybe they are...  Job security!
> > > > > > >
> > > > > > >
> > > > > > > On Wed, May 23, 2018 at 7:14 PM, David Lambert <
> > > [email protected]
> > > > >
> > > > > > > wrote:
> > > > > > >
> > > > > > >> Our credit union had used employee numbers for account
> numbers.
> > > But
> > > > > ran
> > > > > > >> out of 5 digit numbers.  Did they change our accounts to
> 0abcde?
> > > > No!
> > > > > > >> They
> > > > > > >> multiplied 10 leaving us as abcde0.
> > > > > > >> ------------------------------------------------------------
> > > > > ----------
> >
> > > ----------------------------------------------------------------------
> > > For information about J forums see http://www.jsoftware.com/forums.htm
> > ----------------------------------------------------------------------
> > For information about J forums see http://www.jsoftware.com/forums.htm
> >
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