On 15/12/2013 4:27 PM, Raul Miller wrote:
On Sun, Dec 15, 2013 at 5:56 PM, Don Kelly <d...@shaw.ca> wrote:
And that's what this -@^.@rms bit is doing - finding that angle.
What you have noted threw me (NB.root mean square)isn't that but is a root
(sum of squares) -really a 'distance'.
(on a plane for the white-black point fixed) between points - apparently
angles in this case (although the original example gave
a magnitude rather than an angle)
Yes. That phrase "rms" was one I picked up in high school electronics
class. But wikipedia suggests that it has some general use:
http://en.wikipedia.org/wiki/Root_mean_square
There is a situation where the 'rms' works in the form that you have
used- that is in the case where you have a sum of rms values
and the rms equivalent is %:: +/ *: values. This has been done with
hoisting motors to get an equivalent HP load or for a signal with a
number of discrete frequencies.
What you have done looks damned good.
and you are then getting the log of 1/this distance.
However, not having ground through your work (and maybe not yet competent
enough in J to do so) I am missing a lot
Is there a need to use -^. or -log rather than the raw "distance"?
Good question.
Experimenting: the - is necessary and the ^. is not necessary. (I do
not get a hexagon without the minus, I do get a hexagon without the
^.).
As for meaning - meaning is something we assign to observations.
Whether it's useful or not depends on our tastes and goals (and this
can involve a fair bit of experimentalism and thought sometimes).
Agreed - and a curse/benefit of J is that there are so many different ways
to handle a problem
It's not just J - this is a characteristic of mathematics and of human
thought. (And of other programming languages - though their
vocabularies facilitate different kinds of conversations.)
A nice thing about J is that some experiments become easy and it's
compact enough that conversations about code samples do not
necessarily require too much supporting effort..
Agreed- there is more than one way to skin a cat but J per se (and
APL) lets the computer deal with a lot of the overhead without
interfering with the core of the problem.
Thanks to you,
Don
Thanks,
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