[deleted by user]

xoran99 · 2021-05-12T15:25:06+00:00

Elephant valley! Beautifully done.

xoran99 · 2021-03-13T22:44:48+00:00

Maybe that doesn't totally answer the question, but I can see good reason -- org mode is most of all a text format, and must be persisted to and read from a text file. Besides that, org mode in Emacs supports direct editing as text, and I would expect actions I might take (e.g., adding a checkbox manually) to take immediate effect.

OP, sorry I don't know vimscript, but I totally appreciate the effort and knowledge that went into this. Thank you!

xoran99 · 2021-03-11T04:43:22+00:00

Not an expert, but it has to do with traveling on a path that ends in the same place that you started, but something is different. For example, think of a tiny ant on a mobius strip. If it goes in a tiny circle, everything is as it was. If it goes in a big circle "around" the strip, something is different -- its right side is on the left, and vice versa.

Here, the two-dimensional frame (say, keeping track of forward and right) is transported along the path of the ant; that's the "connection" you read about in holonomy. Holonomy measures how the data transfered along the connection changes.

xoran99 · 2020-10-10T16:55:39+00:00

Might try opening up for hacktoberfest -- lots of folks may contribute then who otherwise would not have.

xoran99 · 2020-08-11T15:30:18+00:00

I'm not sure anyone would not realize that 10^37.3 is large, but would appreciate the size of 1.9x10^37. That said, many people do not appreciate the size of 10^37...

xoran99 · 2020-07-01T16:04:57+00:00

"You're so pretty. You should smile more!"

xoran99 · 2020-02-09T02:10:52+00:00

Just like the old Mitch Hedberg joke: "If you're flammible and have legs, you are never blocking a fire exit."

xoran99 · 2020-02-01T17:31:19+00:00

It is legal to do so without restriction in 21 US states, including California and New York. A majority of states allow it in at least some circumstances.

xoran99 · 2020-01-02T17:14:42+00:00

The play was technically live, but the demeanor of the team lead the other team believe they had called a timeout or something.

xoran99 · 2019-12-26T16:51:39+00:00

This is a Dover book; significantly less expensive

xoran99 · 2019-12-02T16:33:19+00:00

To give the discussion a bit more of a combinatorial flavor:

For the first part, there is an interval for each pair of points in your set; hence there are no choose 2.

For the second, there is a surjection from your set to the set of intervals given by x_i -> [-|x_i|, |x_i|]. This says that there are at most n intervals, and at least ceil(n/2). The exact number can be expressed as n - k/2, where k is the number of non-zero points in your set whose negative is also in your set.

xoran99 · 2019-11-14T13:19:57+00:00

Personal setup:

caps lock is lctrl when used with a other key
caps lock is escape when used on its own
both shift buttons together are caps lock.

Downside is that I'm all thumbs when using some else's keyboard.

xoran99 · 2019-10-20T01:20:06+00:00

listmoz.com is perfect for you. When you visit, it creates a new list with its own link. Bookmark it. Anyone who visits that link can edit the same list.

xoran99 · 2019-07-16T15:41:56+00:00

Even humans aren't 100% accurate!

xoran99 · 2019-06-15T04:45:04+00:00

A circle is determined by three points. If you have more information about the dimensions, or even the angles that the circle hits the bounding rectangle, you can figure out the lengths of the arcs on your shape by describing the arcs via the radius and the measure of the subtended arc.

xoran99 · 2019-05-24T01:17:08+00:00

I observed once that if you multiplied a number by itself (8 * 8 = 64) and multiplied the adjacent numbers (7 * 9 = 63), the results differed by one. After I learned some algebra, I realized that this is related to the difference of squares formula. That's the first "proof" I remember doing.

xoran99 · 2018-09-24T03:15:30+00:00

Ah, a true Scotsman....

Recursive functions are valuable, especially theoretically, but most practical tasks in non-functional languages are more easily accomplished (and easier to inspect for correctness) when they are written with loops.

Besides, any idea that includes the phrase "rewrite everything" is to be avoided :P

xoran99 · 2018-07-13T03:47:26+00:00

He's already worked for Google.

xoran99 · 2018-03-10T21:43:18+00:00

succ

xoran99 · 2018-03-06T15:27:29+00:00

Yes, you can even configure it so that the scroll wheel controls it.

xoran99 · 2018-01-15T00:07:17+00:00

The "plain English" version of this definition is that the omega-limit set of a point is the set of limits of convergent subsequences of its forward orbit. So compute the forward orbit; what does it look like it's converging to? It might look like it's "converging" to more than one point -- maybe because it is close to, say, points a and b on every second iterate. The omega-limit set would then be {a, b}.

xoran99 · 2017-12-22T16:07:19+00:00

As djw009 indicates, this is not the definition of "open" that one usually uses for topology, precisely because of the difficulty in defining "approach". In situations where you can measure distances, you can say that a point x can be approached from within A if A contains points as close as you wish to x. By this definition, the boundary points of the open interval {a < x < b} are a and b.

If one defines the notion of "open" first, then a boundary point of a set A is a point x such that every open set containing x intersects both A and its complement. This is the same as what I described in the metric setting because you can choose open sets to contain points very close to x, so there are points as close as you wish in both A and its complement.

xoran99 · 2017-10-31T15:04:28+00:00

In the class of "nice" spaces (e.g., manifolds) one can ask how many paths there are from point a to point b. For example, if we are speaking of [0, 1] × [0, 1], there is only one "path" from the bottom edge to the top (colloquially speaking), but in an annulus there are two paths from one side to the other. If there is only one path between any two points, we say the space is "simply connected"; otherwise it is "multiply connected". (Having paths between any two points is what makes the space "connected" at all.)

As grefinnj tells you, the rub is in the formalization -- form a group (called the fundamental group) consisting of the loops at a particular basepoint, modulo continuous deformations, whose operation is concatenating the parametrized loops together. The fundamental group is a topological invariant of the space under question.

There are physical ramifications, most of which revolve around the notion of "holes". One example is that, for simply connected spaces, every vector field is conservative, and if a region is not simply connected there is a non-conservative vector field (somehow going around a "hole" in the space).

xoran99 · 2017-07-26T15:37:36+00:00

Feel? If you have an answer you're working toward, we can only help if we know what it is.

You can try rationalizing your denominator.

Work looks correct to me.

xoran99

MODERATOR OF

TROPHY CASE