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The Origin of the Matrix

madmamasmith — Thu, 24 Dec 2009 00:30:53 -0800

Origin of the Matrix relating to a Science Fictional setting... I am reading Neuromancer by William Gibson and the main character mentions "the matrix", as something he "jacks in to". Now this is my first foray into sci-fi and I am only about 20 pages in but I was wondering where the term originated. Did The Matrix movie steal this term and its meaning from Gibson or was it already being used in previous sci-fi works? I have only ever heard it used in a sci-fi context so that's why I;m wondering. I'm admitting my lack of knowledge in this area, so please don't make me feel like a ding dong if the answer to this question is blindingly obvious to you! Also, while on the topic of Sci-fi, the last book I read in the genre was Ender's Game in junior high and I loved it, so please suggest any sci-fi reads I should check out.

Excel: Incrementing Formula Row Copied Across Columns

Conrad Cornelius o'Donald o'Dell — Sat, 07 Nov 2009 13:38:36 -0800

Excel question: I need a row number to automatically increment as I copy a formula horizontally across columns. Sample spreadsheet downloadable here, or viewable as a Google Doc here. Further details inside. To elaborate, the formula in question starts in Column T. In T2, the formula compares Node 1 to itself - hence the zero. In T2, it compares Node 1 to Node 2, in T3, Node 1 to Node 3, and so on. Column U does the same thing, except it compares Node 2 to Node 1, Node 2 to Node 2, Node 2 to Node 3, and so on. I want to copy out my formula so that all 50 nodes in the matrix are filled in, in this manner.

The formula increments properly when copied vertically. Take a look at the representative portion of the formula right after the ABS in cell T2: ($C$2-$C2). The formula stays "anchored" on Node 1 via the $C$2. The second part, $C2, increments as you copy it down, to $C3, $C4 and so on. (The same is true for the rest of the formula - it just goes ($D$2-$D2), ($E$2-$E2) and so on.)

Now take a look at Column U. The "anchor" changes from $C$2 to $C$3. That's because Node 2 is now the basis for comparison. In Column V, the anchor changes to $C$4, because Node 3 is the basis for comparison.

The thing is, the anchors in Columns U and V were updated by hand. That is to say, if you copy the formula in Column T one cell to the right, nothing increments. I realize that this is "proper" Excel behavior - when you copy formulas horizontally, generally only the column will increment. But I would really love a way to force the row number of the anchor to automatically increment as I copy the formula to the right. (Note that the anchor has to retain the $ before the row number because when I copy the formula down, that portion of the formula must stay fixed.)

Please let me know if you need any further clarifications. And if you have any suggestions, I would be very grateful. Thank you.

Can I use the Time Management Matrix in my software?

Anonymous — Wed, 29 Jul 2009 14:07:18 -0800

Can I use the "Time Management Matrix" in a commercial software product without any legal repercussions? (If you're not familiar with the Time Management Matrix, you can find a good primer here.)

My understanding is that the Matrix was popularized by Stephen Covey's book First Things First, and was later featured in some of his other books. Since then it has been widely used in motivational and leadership books and seminars. There are dozens of articles and pages about it online. It very likely existed in other forms, at least in concept, before Covey wrote about it.

I am interested in including a visual representation, description, and interactive version of this Matrix in a piece of commercial software I am writing. Without giving away too much of the application's functionality, essentially a user will be able to click one of the quadrants of the Matrix to assign a task to it, view a list of tasks sorted by quadrant, etc. The software would also include a brief description of the Matrix and its quadrants, with no direct quotations from Covey's book or any other sources. In fact, I don't plan on mentioning Covey at all (unless I must for attribution) in order to avoid any implications of endorsement.

Would I run into any legal issues if I do this? I can't find any solid evidence on whether Covey invented the concept or the term, so that's the first thing I need to find out. After that, I need to know what I can do if he does have some claim of ownership to it.

How to maximise a matrix subject to constraints?

muhonnin — Sun, 14 Jun 2009 05:16:45 -0800

Optimisation problem: trying to find the subset of my data that meets a couple of constraints. I have a data set with 200 columns and 20 rows of numbers. I am trying to find the 20 columns that make the mean of all values in the resulting 20 x 20 data set as large as possible--subject to the constraint that no row in the 20 x 20 set can have a mean value below a particular figure.

I have access to a range of software tools (Excel, Mathematica, SPSS). I know how to specify the constraint if I were going for a brute force solution, but obviously that's not going to be feasible here. All suggestions greatly appreciated. . . . .

The science of suckiness

handybitesize — Mon, 08 Jun 2009 10:07:15 -0800

I want to calculate the mean of a matrix, but I don't want a value, I want co-ordinates. The following math question has lots of terminology that I'm not qualified to use i.e. most of it is wrong. I hope you can see through this and help me. I will be using the words matrix, mean and transformation without fully understanding them. For this I apologize. Imagine a 10x10 matrix of integers, I wish to find the 'point of balance'. That is, if the integers were weights and the matrix a sheet of plywood, it is where I would place a pivot for the sheet to remain in balance (assume the plywood has no weight).

I don't want to work it our mechanically (using trig and moments and things of that ilk, besides the weight thing is an analogy, I'm looking at luminosity), I want to apply a matrix transformation if possible.

However my knowledge doesn't even let me begin to search on the type of transformation I need.

I have played with the mean of the rows and cols. In a 2x2 matrix for example

10,20
4,200

x = ((1 * 10) + (2 * 20) + (1 * 4) + (2 * 200)) / (10 + 20 + 4 + 200) = 1.94017094
y = ((1 * 10) + (2 * 4) + (1 * 20) + (2 * 200)) / (10 + 20 + 4 + 200) = 1.87179487

which looks right, but doesn't feel right. I'm sure we are missing something.

Any pointers/equations/corrections are very appreciated.

(The 'suckiness' in the title refers to the larger integers "sucking" the balance point towards them, not that I suck at science, which I do)

Maximizing a function over orthogonal matrices

a robot made out of meat — Sun, 26 Oct 2008 08:26:48 -0800

Maximizing a function over orthogonal matrices, or: solving polynomial order 2 systems. Help me out or point me to a better forum / listhost. I have a function f(T) of a matrix that I want to maximize, which is order two in the elements of T. Easy, partial derivatives gives you a linear system. Here's the catch; I also want T to be orthonormal (the dot product of the rows to be zero or one -- the extension of orthogonal to non-square matrices).

The obvious way to maximize a function with constraints is to tack on Lagrange multipliers g(T) = f(T) + sum{lambda[ij](Ti . Tj - delta(i,j) ) }, but now g(T) is order three in parameters, and partial derivatives are order two and I don't know how to solve that system generally.

The dimension of T can be huge, tens of thousands. Let's not suggest numerics unless there's an amazing trick to deal with the dimensionality.

Any ideas? Maximization subject to orthogonality seems like something that should have come up a lot and someone have figured out.

How can I rotate around 3 axes in opengl?

mebibyte — Tue, 14 Oct 2008 14:17:37 -0800

Please help me wrap my head around this 3d graphics math. :( I'm writing an application in OpenGL for learning purposes and I'm trying to allow the user to modify the angle by which I rotate an object around the X axis, the Y axis, and the Z axis.

My problem is that I only know how to do the following:

glRotatef(xAngle,1,0,0);
glRotatef(yAngle,0,1,0);
glRotatef(zAngle,0,0,1);

(basically, rotate around the x axis, then around the y axis, then around the z axis)

This doesn't work because, essentially, after rotating, say, 90 degrees about the x-axis, the y and z axes are no longer where they used to be. See this crude picture for more information on what I'm talking about.

What I'm looking for is best practice on what to do in this situation. I have two opengl books and I've searched the internet and I haven't been able to find out anything about this. Surely this must be a common problem?

Code or (well-explained, not dry) math theory would be much appreciated. Thanks!

how do you construct a correlation matrix in APA format in Microsoft Word 2007

esolo — Sat, 14 Jun 2008 13:12:39 -0800

how do you construct a correlation matrix in APA format in Microsoft Word 2007 without killing yourself? I have 12 variables, and I need to construct a matrix of correlations preferably in portrait orientation. I have spent hours on this, and I still can't get my table to look like it should.

Each cell with correlation value should hold at least 5 characters. Is there a tool out there that would help me do that? APA came out with a plug-in, but it doesn't work with MS 2007, which is what I have. Please help!

The (Monotype) Matrix Reloaded

scruss — Thu, 20 Mar 2008 18:22:39 -0800

I have a Monotype matrix case containing a bespoke font. Please help me see what it looks like in print. I worked for a publisher that used to commission its own typography. They shut down their printing plant many years ago, and much later, a senior editor gave me a type casting matrix case which they'd rescued from the dump.

The font looks to be an elegant book font. There is a code stamped on the case "403-11", which might be the (British) Monotype reference for that font.

Is there anywhere (in North America; Canada preferred) I could get samples printed of this font? The back of the matrix case is pretty beat-up; looks like a lot of type was cast from this font. The brass matrices appear to be clean, though.

My ideal would be to have this digitized into an outline font, but to do this properly would take time, money and skill. I have none of these.

What is this symbol that looks like an O with a small n or r in it?

i love cheese — Fri, 02 Nov 2007 08:54:23 -0800

What is this logical/matrix/algorithm symbol? I'm trying to implement an algorithm for manipulating matrices and I think I understand the equation described, but I don't know what the symbol that looks like a big O with a small n or r in it is called, or what it really means.

The actual computation seems to be a calculation of Minkowski distance having exactly i+1 links, and that it relies on knowing the distance having i links. I've never seen that symbol before, and would like to know what it means

Where can I find an aftermarket 16" wheel cover for a 2005 Totoya Matrix?

dy — Thu, 25 Oct 2007 12:03:42 -0800

Where can I find an aftermarket 16" wheel cover for a 2005 Totoya Matrix? I lost one of the wheel covers of my 2005 Toyota Matrix the other day while I was driving. I thought it's something easy and cheap to replace. I went to Walmart and Pepboys, and they both carry wheel covers up to a size of 15". Mine is 16" and was told I had to go to dealer for a replacement. Technically, I don't believe a Toyota cover will be any superior to what Walmart is selling - it's all plastic, and Toyato will charge 5x more easily. Is there any place that I can go to for a whatever brand wheel cover, relatively in the Walmart or Pepboys kinda price range for a set of 4? I live in Orange County, CA. So any where in OC or LA will work, or online. Thanks a lot.

Profession Matrix

pmaxwell — Sat, 25 Aug 2007 23:33:02 -0800

I want to map out every possible profession / career. How would I start? From major categories like medicine, arts or technology then drill down to their subsets of phlebology, foley artist and Systems Analyst, for example – and everything in between. How would one define the umbrella areas and begin the task of defining a hierarchy of professions under each?

Help Me Find These Sunglasses!

Phyltre — Wed, 07 Feb 2007 20:55:20 -0800

Looking for help categorizing/finding a particular style of sunglasses, harder than it sounds! Okay, I've been looking for a particular type of sunglasses for quite awhile now. I've found precious few examples, mostly through imitations from movies, etc. The sunglasses I want are similar to what Seraph wore in the Matrix (http://www.maximumeyewear.com/productfolder/celebrity-sunglasses/movie-sunglasses/matrix-sunglasses/matrix-glasses.jpg) but perhaps slightly smaller around the eyes. I've tried buying the cheap replicas of these, only to find them to actually be generic round eyeglasses quite unlike the photo. Apparently no "real" consumer versions were made, unlike the others released by Blinde.

I'm looking for what I can best describe as "assassin" glasses, small round black lenses that are close to each other between the eyes (not Morpheus glasses, though. These are different.) They're sometimes referred to as "John Lennon" sunglasses but obviously I want the lenses to be smaller. I've seen the exact style in several movies, and animes, and even in the windows of a few sunglasses shops (back in high school; of course they don't have them anymore.) This leads me to believe that this actually was fashionable somewhere at some time, and that this is an actual style. Usually killers, villians, or older wise characters wear them in movies.

I've spent at least 15 hours trying to chase down exactly what to call this style, and googling generic terms like "round", "Lennon", etc. but I haven't made much progress. Can anyone help me out? And can anyone tell me where to find them?

Wall Graphics

Sreiny — Sun, 15 Oct 2006 20:33:25 -0800

Converting an image to a simple dot-matrix pattern? A section of my wall is concrete and so I can't hang anything on it. I am planning on buying a few thousand color labels and creating an image in a dot-matrix style. This is a bad example
but kind of along the lines of what I'm thinking of doing, except with an image. Is there a program or application that I can download to convert an image to a dot matrix grid. Basically what I'll do is set up a grid in Illustrator to plan it out, and either there'll be a sticker there, or there won't.

To focus the answers a bit, this isn't a job for Rasterbator or photoshop halftone filter, it needs to be gridded with an "either there's a dot there or there isn't process." Thanks.

Korean Language Matrix Trilogy

billtron — Sun, 15 Oct 2006 01:21:04 -0800

Looking for all three Matrix films, region 1 DVD or VHS, either dubbed or subtitled in Korean. Can you help me?

How to search an interior matrix/array and lookup a corresponding value in Excel?

brettcar — Fri, 21 Jul 2006 13:26:25 -0800

Excel Powers Active! Vague Excel spreadsheet lookup problem inside. On preview, I apologize for the messy table below but it should make enough sense. I've got a fairly large Excel table that looks something like this:



     ColA            ColB              ColC                  ColD

1   Index1        Moretext       Evenmore          Don't_care...

2   Index2        Stilldifferent  Veryfrustarting  Don't_care...

3   .....

4   .....

What I would like to do is provide a search key, that should appear in Column B or Column C. And what gets returned is the value in Column A. So if I searched for 'Evenmore' I would get 'Index1' and if I searched for 'Stilldifferent' I would get 'Index2'.

To complicate things, I don't want to search beyond column C.

In reality, I actually have different strings in Columns B to I, and the value I want to look up is in Column A, J, K, or L. I have just simplified the diagram above for your comprehension pleasure. The number of rows is 255, but this could grow. Thanks in advance!

Notes Towards A List Of Post-Matrix Films

ninebelow — Thu, 09 Mar 2006 02:23:17 -0800

Post-Matrix films? What action films are clearly post-Matrix? Not neccessarily science fiction but probably. Guns, martial arts, wire work, bullet-time, excessive slo-mo, etc. So for example: Equalibrium and Ultraviolet.

How do I create user-defined mathcad functions that take matricies as arguments and returns a matrix.

nickerbocker — Mon, 21 Nov 2005 20:00:19 -0800

How do I create user-defined mathcad functions that take matricies as arguments and returns a matrix? There are built-in functions that take and return matricies. I've looked through help and the manual but can't come up with how to write a function that does the same. Please help!

How does one learn to cope with technology?

jdroth — Thu, 21 Jul 2005 10:18:14 -0800

When I leave the 'grid' for vacation — weekend or week-long, it does not matter — I feel liberated. Free. Refreshed. When I return, ubiquitous media (especially television and internet) really get me down. Then, after a few days, I'm back on the grid, sucking from the teat of technology. I feel dirty. And guilty. Still, I love technology. It's like I'm addicted (especially to the internet), and only quitting cold-turkey helps. How does one cope with technology? Without becoming a Luddite, how does one break free of the addiction? How does one find balance? Note that I mean all technology — cars and phones and iPods, too — not just television and internet.

Excel spreadsheet question

Kwantsar — Thu, 23 Jun 2005 09:08:04 -0800

I have a complicated Excel valuation spreadsheet. The "bottom line" is affected by about 20 variables. I'm comfortable fixing about 17 of them, but for the remaining three, I wish to output to a 4x30 matrix, consisting of parameters A, B, and C, and the bottom line value that corresponds to each of the three. As it stands now, I can plug and chug, but it's a bit unwieldy, and I may wish to make a bigger matrix soon (I'll keep the 4 parameters, but I may wish to go 4x100 or the like). I can't reverse engineer the entire spreadsheet-- it would take forever. So, how do I build this matrix? In other words. as it now stands, I fill the three cells manually and cut and paste the given "answer" to a hand-crafted matrix, but I want to be able to draw the matrix and have the spreadsheet put the answers for each set of parameters in the fourth column.

I realize that I may have phrased this question poorly. I'll try to respond to subsequent questions.

"Lana" Wachowski

jimmy — Mon, 02 May 2005 14:33:54 -0800

Around a year and a half ago, it was rumored that Larry Wachowski (co-creator of "The Matrix") was to undergo a sex change operation. Did anything ever come of this? I tried Googling it, but was only able to find the original story, with no follow-up.

Lexis Nexis: Check the Matrix!

exhilaration — Mon, 06 Dec 2004 12:32:51 -0800

Can someone check Lexis Nexis to see if this case is real: Sofia Stewart vs Andy and Larry Wachowski, Joel Silver and Warner Brothers, United States District Court of California? Boing Boing says that the Matrix was stolen by the Wachowski Brothers from Sofia Stewart and they lost a court fight but the only source is a college newspaper! The only thing I found on Google was some guy saying that the details were on Lexis Nexis.

Matrix Furniture

tirade — Tue, 06 Jan 2004 11:11:49 -0800

Does anyone know who makes the chair that Agent Smith wheels over and sits down in while interrogating Morpheus in the first Matrix movie?