John Robertson

North Salt Lake, UT

john.jersdesk.com

Age: 43

I am a software developer. I am particularly fond of the areas:

  • artificial intelligence, computer vision & machine learning
  • high end graphics & image processing
  • games

As this profile is now posted across multiple sites:

I am a member of the Church of Jesus Christ of Latter-Day Saints, also known as a Mormon.
I am also a mathematician.
I quite like interesting games and enjoy playing them with those of my many wonderful children who are old enough. We will often edit what we might find to be sleazy in a game without altering the game play, which quite widens the range of games we can play while staying within what we consider to be gospel standards.

2d
awarded Taxonomist
May
25
awarded Popular Question
May
23
awarded Teacher
May
23
comment Is every closed curve in 3D a geodesic on a genus-0 surface?
No, this is no proof. Yes, it is probably the way you could make a proof. As long as you can embed the curve in the surface of a smooth ball the answer would be yes by "inflating" the sphere a small amount except for a "trench" which contains the curve. The base of the trench also needs to be modified by being angled to be perpendicular to the plane of a best fit circle to the curve at that point. No time for anything better. But I think that is the outline of how you prove it.
May
19
answered Fastest way to comment out multiple lines in Notepad++
May
19
comment Is $\frac{\textrm{d}y}{\textrm{d}x}$ not a ratio?
But it gives the wrong idea, because dx and dy are perfectly well defined 1-forms (they act on tangent vectors, not points). And their ratio is constant on fibers (i.e. it depends only on the base point of the vector) and so it descends to a well defined function which is exactly f'(x).
May
19
accepted Referencing object's own properties in javascript
May
19
comment Referencing object's own properties in javascript
So there is not a way to reference an objects own properties within an objects own methods except by using "this"? If I have properties x,y to add and put into property z I need to write out this.z = this.x + this.y?
May
19
comment Referencing object's own properties in javascript
@Daniel Yes, that is an excellent reference on "this", but I am not asking whether "this" refers to the property, but what happens when I omit "this".
May
19
asked Referencing object's own properties in javascript
May
18
comment Is $\frac{\textrm{d}y}{\textrm{d}x}$ not a ratio?
-1 I'm sorry, but this is based on a misapprehension. The dy/dx is for the the goemetric entities which are the level curves, the partial derivatives are for the function we are taking level curves from. This doesn't demonstrate what it is claimed to as we are using a different entity on the left than on the right.
May
18
awarded Critic
May
15
comment Image scaling by CSS: is there a webkit alternative for -moz-crisp-edges?
As of May 2015 this answer does not give pixelated results on the current version of IE.
May
14
comment How link a javascript file to an html file
How can this not be a real question? It is a straightforward syntax question. Straightforward javascript asnwers that aren't w3schools can actually be a bit hard to find.
May
14
awarded Cleanup
May
11
comment How many axes did Gimli bring on the quest of the Fellowship?
Besides, Tolkien had at least some experience in a real military at real war time (others certainly know more about this). Silly things like throwing away your weapon at every opportunity probably never crossed his mind.
May
10
awarded Notable Question
May
6
awarded Yearling
May
6
awarded Yearling
May
6
answered Absolute positioning inside relative positioning?
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