2023-09-13 03:48:45 <KipIngram   > Ok, sometimes is the simple little things that are satisfying.  Watching a Wildberger video.  Simple stuff; he's introducing the basic principles for later.  So, I've always known that if you have two lines ax+by=c and dx+ey=f, you can go through a bit of a rigamarole and find their point of intersection.  Little system of equations, solve it, etc.
2023-09-13 03:49:01 <KipIngram   > But what he just demonstrated is that you can place your lines in what's called the "projective form":
2023-09-13 03:49:25 <KipIngram   > (-c, a, b) and (-f, d, e).
2023-09-13 03:50:01 <KipIngram   > You can put points in projective form too; the point x, y gets written as [1, x, y].  Note the [] for points and () for lines.
2023-09-13 03:50:31 <KipIngram   > Anyway, now the components of the point of intersection of your two lines is just the components of the cross product of the two projective lines.
2023-09-13 03:50:35 <KipIngram   > Bam bam and done.
2023-09-13 03:50:49 <KipIngram   > I know it's ultimately the same arithmetic, but it's PACKAGED in a much more conceptually simple way.
2023-09-13 03:51:21 <KipIngram   > And, what's even cooler, is that there's a duality.  If you have two POINTS and want the LINE that they form, the components of that are exactly the same thing: the components of the cross product of the two projective points.
2023-09-13 03:51:26 <KipIngram   > now that is just quite cool.
2023-09-13 03:51:52 <KipIngram   > So the cross product arithmetic just flips you back and forth between the two "meanings."
2023-09-13 05:47:27 <KipIngram   > xelbar: I think something like foo←4 4⍴0 will give me a dictionary entry foo which will behave as a Forth variable - executing it will leave it's address on the stack.  And of course it's initialized a 4x4 integer array.
2023-09-13 05:48:00 <KipIngram   > Now, I DON'T know if that's going to create a standad Forth header.  The namespaces may not mingle exactly that way.
2023-09-13 05:48:37 <KipIngram   > I haven't thought yet about how to make Forth aware of APL symbols, or vice versa.
2023-09-13 07:20:01 <xelxebar    > KipIngram: Forth dictionary doesn't really play well with growable data, right? Something like `A←1 0 1 ⋄ A←1e6⍴A` would probably need to create a whole new A.
2023-09-13 07:22:45 <xelxebar    > I wonder if it should be turned on its head. Probably easier to emulate a stack as an APL array than the other way around.
2023-09-13 07:23:58 <xelxebar    > Should we, instead, be thinking how bootstrap an APL minimalistically a la Forth spirit?
2023-09-13 12:36:46 <KipIngram   > I'm not talking about the data - talking about the header.
2023-09-13 12:37:43 <KipIngram   > I'll need some kind of "management of RAM I'm sure.
2023-09-13 12:38:16 <KipIngram   > I was talking there just about the name.
2023-09-13 12:38:51 <KipIngram   > I feel sure I'll need a heap of some kind.
2023-09-13 12:44:04 <Zarutian_iPad> a heap of trouble?
2023-09-13 13:00:24 <KipIngram   > Heh.  Yeah, likely.  :-)
2023-09-13 13:01:46 <KipIngram   > Anyway, I think being "type aware" and having the kind of dynamics I expect from a scientific computing facility will require a heap, and the stack will only ever contain pointers into the heap.  And likely named variables will also only hold pointers.
2023-09-13 13:02:55 <KipIngram   > You wouldn't technically have to handle integers that way - they could still be "native" integers, but my guess is that a totally consistent approach over all data types will be desirable.
2023-09-13 13:08:37 <rendar      > historically Forth used kebab-case or lisp-case? e.g. `1 2 3 my-word` ?
2023-09-13 13:21:13 <veltas      > Yeah
2023-09-13 13:21:41 <veltas      > KipIngram: I suppose I'm not a novice but I'm not an oldie or an expert
2023-09-13 13:22:19 <veltas      > Part of reason I seem more knowledgeable is because Forth is simple and approachable
2023-09-13 16:06:16 <KipIngram   > rendar: I don't really associate that sort of "case discussion" with Forth very much.  The main naming advice I've seen is "try to choose names that lead you to a 'lexicon' for your application."
2023-09-13 16:06:42 <KipIngram   > Running your application should be almost like "talking about the application."
2023-09-13 16:06:56 <KipIngram   > So you'd use words that were already familiar in that particular area and so on.
2023-09-13 16:07:10 <KipIngram   > Make the application seem intuitive to people familiar with the field.
2023-09-13 16:07:43 <KipIngram   > Personally I tend toward short names, all lower case, and often feature symbols.
2023-09-13 16:08:12 <KipIngram   > I like an almost mathematical notation.
2023-09-13 16:08:31 <rendar      > KipIngram, yeah i agree
2023-09-13 16:09:08 <KipIngram   > So I'm still watching Wildberger videos.  He's going through Bernoulli's approach to summing powers, which has use in evaluating slowly converging power series and so on.
2023-09-13 16:09:21 <KipIngram   > It feels like another topic that "should be taught routinely and isn't."
2023-09-13 16:09:34 <KipIngram   > I've really begun to notice how "minimalist" our public education has become.
2023-09-13 16:09:43 <KipIngram   > They just set a really, really low bar.
2023-09-13 16:09:56 <vms14       > https://i.imgur.io/mKyVTnL_d.webp?maxwidth=640&shape=thumb&fidelity=medium
2023-09-13 16:10:01 <vms14       > ahahahahaha
2023-09-13 16:10:37 <KipIngram   > My cat is nice too.
2023-09-13 16:11:28 <vms14       > i did not know my lang supported emojis
2023-09-13 16:11:33 <KipIngram   > We have two cats and two dogs, and I like all of them, but I'm just particularly sweet on one of the cats.
2023-09-13 16:11:42 <vms14       > :o
2023-09-13 16:11:47 <vms14       > i want a cat
2023-09-13 16:11:53 <KipIngram   > Cats are awesome.
2023-09-13 16:12:30 <KipIngram   > He had a whole pile of medical difficulties his first couple of years - I think taking care of him through all that made me feel more strongly toward him.
2023-09-13 16:12:49 <vms14       > note how the word redefinition affects other words btw
2023-09-13 16:13:31 <KipIngram   > And the story of how we got him is really good.  My wife found him on the neighborhood Facebook page.  A guy who works in downtown Houston (like 30 - 40 minutes away) left work one day and headed home on the interstate.
2023-09-13 16:13:34 <KipIngram   > It was winter.
2023-09-13 16:13:46 <KipIngram   > After a few minutes he started to hear mewling / screaming.
2023-09-13 16:13:58 <vms14       > 💦 returned a list, but later was redefined to return 1 2 3
2023-09-13 16:14:02 <KipIngram   > The kitten had crawled up into his truck engine, no doubt because it was warm.
2023-09-13 16:14:09 <KipIngram   > and was still there when the guy started driving.
2023-09-13 16:14:18 <KipIngram   > It's a miracle he survived it.
2023-09-13 16:14:29 <vms14       > oh did not change it's definition, but just uses the last definition as the other no longer exists
2023-09-13 16:14:32 <KipIngram   > Anyway, it got hot and he started to cry - his little foot pads were burned etc.
2023-09-13 16:14:45 <KipIngram   > We took him in, and he's been terrific.
2023-09-13 16:14:48 <KipIngram   > Apollo.
2023-09-13 16:15:16 <KipIngram   > He's almost four.
2023-09-13 16:15:24 <vms14       > it's a bit sad actually
2023-09-13 16:16:02 <vms14       > that's why you say you are sweet with this one
2023-09-13 16:16:15 <KipIngram   > Anyway, the other education thing this made me think of was dimensional analysis, which just really isn't taught SERIOUSLY in engineering curricula anymore.
2023-09-13 16:16:33 <KipIngram   > The may mention it, but what they're talking about is in no way as sophisticated as the subject gets.
2023-09-13 16:16:55 <KipIngram   > I found a good paper on it one day and all while reading it I was just thinking WHY DO THEY NOT TEACH THIS?????
2023-09-13 16:17:24 <KipIngram   > It's almost as though the attitude is "If we can find a way to avoid it, we will."
2023-09-13 16:21:13 <vms14       > i wouldn't expect too much from university
2023-09-13 16:26:53 <KipIngram   > I think there's an aversion these days to having "differences" show between the best and worst students.   They want a "homogeneity."
2023-09-13 16:31:45 <vms14       > i wonder about representing statements as objects
2023-09-13 16:31:58 <vms14       > like you have a loop object
2023-09-13 16:32:09 <vms14       > or iterator object
2023-09-13 16:40:18 <KipIngram   > That HP RPL lets you store code strings in variables.
2023-09-13 16:40:34 <KipIngram   > In fact that seems to be its primary way of storing code.
2023-09-13 16:50:31 <vms14       > i use lists as code
2023-09-13 16:50:43 <vms14       > like a colon word
2023-09-13 16:51:10 <vms14       > i'm wondering lately if making ( execute actual lisp code
2023-09-13 16:51:34 <vms14       > i could have a way to get an element from the stack
2023-09-13 16:51:55 <vms14       > and it would use the same environments so variables would be available there
2023-09-13 16:52:40 <vms14       > i always wanted to have a word like 'lisp' that takes a list and executes it as lisp code
2023-09-13 16:53:06 <vms14       > but optional arguments and alike make it a bit hard to blend with a stack based lang
2023-09-13 16:53:14 <vms14       > well it's not
2023-09-13 16:53:39 <vms14       > a lot of languages use a stack internally
2023-09-13 17:05:39 <veltas      > KipIngram: This is a thing I've heard of before, cats crawling into enginers
2023-09-13 17:05:44 <veltas      > engines*
2023-09-13 17:05:53 <veltas      > Apparently if you park with wheels straight they can't get in (as easy)
2023-09-13 18:07:42 <KipIngram   > Interesting.   Anyway, that guy's family didn't feel like they could add a cat, so they posted and my wife just saw him and decided we needed him.  We had just lost our family dog a few months before - she first said "No more pets," but I think by the time of these events she'd gotten through part of the mourning process.
2023-09-13 18:09:49 <thrig       > cats aren't pets, they have staff
2023-09-13 18:14:50 <KipIngram   > :-)
2023-09-13 18:14:55 <KipIngram   > Or maybe we're their pets.
2023-09-13 18:15:04 <KipIngram   > They graciously share their home with us.
2023-09-13 18:15:26 <KipIngram   > My wife read me a joke once.  I probably won't get it quite right, but it ran like this:
2023-09-13 18:16:14 <KipIngram   > Dog: "They feed me.  They take care of me.  They play with me.  They must be gods."  Cat: "They feed me.  They take care of me.  They play with me.  I must be a god."
2023-09-13 23:43:16 <xelxebar    > Oooo. Dimensional analysis. It dawned on me not too long ago that it's essentially a kind of type inference.
2023-09-13 23:44:19 <xelxebar    > I read about someone who, brilliantly, goes a step farther and elaborates beyond the standard types/units.
2023-09-13 23:56:28 <rendar      > so i guess that also words like "ispos?" "isnan?" ">0" "isnil?" should consume the value and put a bool in the stack, right?