Tracy Harms wrote:
> As an example of where my curiosity has wandered, I've not been able to
> decide whether (i: _j_) naturally denotes the Rationals, or only a
> subset of them.
As an interesting tangent, here's an expression that actually does work in
J:
i: _j1
_2147483648 _2147483648
So, in a way, _ *is* being treated as a value (the maximum integer).
Can someone with J64 run the above and post the results?
> (If "_" were taken as a value, which it must not be, it
> would denote the Integers.)
Could you elaborate on this, please? AFAICT, i:_j_ would mean "the
numbers from __ to _ in infinitely many steps". Well, looking at it one
way, i._ is already infinitely many steps, and i:_ is "double
infinitely" many steps (i.e. the j_ clause is actually /reducing/ the
length of the output). The conclusion highlights the absurdity of such
arguments, and it becomes clear that one could as easily argue that i:_j_
would mean "from __ to _ with an infinitesimal step size", and therefore
would denote Q.
-Dan
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