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#176 Re: Help Me ! » Math Terms - Visually Described ? » 2010-12-25 02:12:16
bobbym wrote:The picture in post #197 tells you where to touch with your mouse. Another small box will drop down, touch each one with your mouse and a legend will show up.
When I write in the matrix there are no spaces between the letter like you have ?
You do not have to split the Sx, Sx could be the name of a variable that could equal 23.
What I meant was if you were to read it as a Matrix for each axis that is why I asked if you could lay it out in 3D terms in a matrix formation ?
#177 Re: Help Me ! » Math Terms - Visually Described ? » 2010-12-24 18:14:47
That is true in math in general. The use of letters ( variables ) sort of generalizes statements. When I said an n x n matrix you can substitute any positive integer for n, meaning a 3 x 3 ( 3 by 3, 3 rows, 3 columns ) or 4 x 4 or 100 x 100.
Ohh so letters are used as a variable for example which I know sX could be s34, now I know just replace the letters with numbers !
For the same reason you should not try 873654726534 x 8467214253763 in your head, it is beyond most humans. The error she made was in trying that problem to begin with and not understanding someone was sabotaging her.
HaHa 
I understand !
For latex you can go here, this site uses pull down menus to generate latex.
http://latex.codecogs.com/editor.php
A box will come up asking for the size. Enter 3,3 or 4,4 or 2,2 depending on what you want. A template will appear fill it in with the numbers you want. Now you can post that on a forum. When you have done this come back to me and I will show you how to post it here.
Touch where the picture indicates and more choices will show. Click the one that says \begin{vmatrix}...
I need a legend that explains what each letter means, I don't know where to find /begin ! Why call it a latex editor ?
#178 Re: Help Me ! » Math Terms - Visually Described ? » 2010-12-24 17:07:26
In your first example with the 4x4 matrix what does each column and row represent in 3D ?
Latex is a course almost in itself, especially the way I do it. But I can show you maybe an easy way just for matrices.
Please !
I will try to decipher what that programmer did with his gui when we come to it. You have much to understand first.
How much is much ? 
You are getting confused over nothing. You can take the determinant of any nxn matrix, not just a 4x4. Please, Oh please do not try to take the determinant of a 4x4 with pencil and paper!
Why should you not try to take the determinant of a 4x4 with a pencil and a paper ?
You can take the determinant of any nxn matrix
I have to still learn why the use of letters is so common in matrices.
On public tv over here they have several shows with local teachers giving math instruction. You can call in your questions and they will answer them on the air. Well one day a young attractive woman was the teacher for the show. Now, this guy watching the show gets a brilliant idea. He calls in and asks her to find the determinant of a 4x4 with both positive and negative entries. She writes the problem on the board and begins to work on it right there on tv. After all how hard can it be? She can do 2x2 and 3x3's okay so...She struggles and groans with each error. Soon the blackboard is a mess, this is her fourth try and still not the right answer. Our hero, is rolling on the floor, this sadist, this moron, this cretin. Now I do not want you to confuse that imbecile with me, I would never do such a thing.
What country is this ? Is the show still on TV ? Was the person asking the question you the end of your paragraph made me wonder but not assume ?
I am going to a little break now to eat. In the meantime go over those pages. Merry Christmas and a Happy New Year.
Same to you, I hope that 2011 brings me much fortune financially as well as starting my freelance career and a attractive women as well, it wouldn't hurt As 2010 and most previous years brought alot of grief, but I learned who brought on this grief as well as what I could have done to change. I can only hope for 2011 it turns around !
#179 Re: Help Me ! » Math Terms - Visually Described ? » 2010-12-24 15:13:28
Nope! Those pages are fundamental! They come first. You have no chance of furthering your understanding without them.
That is why I have to study them further while I put some terms to use while I work !
A matrix times a matrix is never a scalar, it is always a matrix. A scalar in plain english is a single number like 5.
I'm going to have to go over what I read again on this
A matrix can be thought of as a bunch of vectors. You do not convert a matrix into a vector.
A matrix x vector = vector.
I don't understand !
You have to use latex to do that.
???
A 4x4 matrix is just a matrix with 4 rows and 4 columns. I have showed you a bunch of them. Nothing special about them.
I know that a 4x4 is identical to a 3x3, it just has that extra row and I was in a discussion on a 3D graphics forum and the word "determent" always occurs when talking about 4x4 that is what confuses me.
On the top of the GUI you will see SRT to Matrix, that is bad terminology. That does not mean something is turned into a matrix. When you put in a number in, an element of one of the matrices in post #185 gets it put in the appropriate box.
Can you explain or break it down what is happening in the image I posted from the program ?
#180 Re: Help Me ! » Math Terms - Visually Described ? » 2010-12-24 14:03:31
Those two web sites were pretty helpful I have to study these pages more though !
When you multiply a matrix by a matrix that creates a scalar, always ?
Dot Product is where you must always match the first row by the first column, or the second row by the second colunm etc?
Is there a site on how Matrix is converted to a Vector ?
How do you post Matrix in this forum so it shows up as a Matrix ?
Do you have any sites that explain what a 4x4 matrices are ?
Here is a simple tree from my 3D program, I sorta understand but maybe you can help me break it down as to what it's doing ?
The first node from left to right shows the properties, each other node just passes though, most of the time 
What I don't understand completely is how a 3x3 matrix works in 3D if each column is X,Y,Z what do the other rows represent ?
#181 Re: Help Me ! » Math Terms - Visually Described ? » 2010-12-22 15:25:13
I don't understand it the matrix graphs you are displaying how do I read them ? You use terms such as sX Y2 etc.
I do not know what that is. As far as I understand, scaling, rotating and translating ( moving ) are each done by a separate matrix as I have given them to you in post #185 as S.
That is exactly what I want to know is understanding how a matrix is broken into a single row matrix ?
How do I multiply a Matrix by a Vector ? Those are some of the questions I have currently. The way I operate some of these math in the 3D program is similar to MatMat, I'm going to post a screen shot of a simple example to break down how it works, for example subtracting adding two vectors if one is at 1.345 and the other is at 3.456 gives me 4.801 round that off or using another math term gives me 4.8 I just thought of something it would be neat if there was a calculator that would work in conjunction with this type of 3D math, it would be helpful but something I would understand while I learn
#182 Re: Help Me ! » Math Terms - Visually Described ? » 2010-12-22 07:15:35
The example you gave I still don't quite understand. I understand what variables are, just so you are away of what I know, and I know the fundamentals of how vectors work, I've already begun working with my 3D programs math and I'm going to post a picture of how it works and the math. In the meantime I want to know how to do the math for a matrix and how to convert a matrix to X,Y,Z.
I know that in 3D matrix each axis has it's own sub-axis so to speak if you want to convert a matrix to these three axis how is that done ?
(0,0,0) = Scale
(0,0,0) = Rotation
(0,0,0) = Movement
#183 Re: Help Me ! » Math Terms - Visually Described ? » 2010-12-21 02:45:18
What I don't understand is the order and what are 5x and 8z represent ?
#184 Re: Help Me ! » Math Terms - Visually Described ? » 2010-12-20 14:58:39
Alright I just want to understand while I put it into practice but begin where you think we shall begin and I'll reply as often as I can throughout.
#185 Re: Help Me ! » Math Terms - Visually Described ? » 2010-12-20 14:38:24
That is what I meant how did you get the forum to write out a Matrix like that ?
Are you saying that is 3 points in xyz? Are you using the convention that each column vector is a point?
Yes that 3 points are in XYZ. As to your second question, I don't understand
At present you do not know how to add or multiply 2x2 or 3x3 matrices or a matrix times a vector. You do not yet know how to get the determinant. You do not know how to plot a point in xyz. If I am wrong then let's move on to Wally's page. But if I am right we need to cover the math first.
I know how to plot a point in XYZ, as for the Matrix math obviously no that is why I resurfaced this thread !
Cause now we will be working with 4 x 4 matrices and 4 x 1 vectors. That is how they can translate a 3 dimensional point onto a 2 dimensional screen, giving it perspective.
Lets begin how to translate then I'm going to show you some math stuff in a image. I can hope you can help me understand something.
#186 Re: Help Me ! » Math Terms - Visually Described ? » 2010-12-20 12:39:41
Scale, Translation & Rotation
(0,0,0) (0,0,0) (0,0,0)
#187 Re: Help Me ! » Math Terms - Visually Described ? » 2010-12-20 12:31:28
First just lay it out on the table how do you convert a 3x3 matrix to SRT
toAnd you forgot about the first set of questions which had "set sum" etc we will go back to matrices but now quite yet
#188 Re: Help Me ! » Math Terms - Visually Described ? » 2010-12-20 11:54:50
How do you figure how to multiply matrices ?
I know if you want to divide matrices you usually do so in 3D by a vector, but how do you convert a 3x3 matrix to X,Y,Z ?
What is a determent in a 4x4 matrix ?
We also covered XYZ. I told you that unless you are willing to cover the math first 3D graphics will be difficult to understand.
I taught you modulo and clamp and how to rotate and translate points in a cartesian system. I say the same things now that I said then, you have 2 choices.1) Many graphic programs and languages will create 3D forms for you. They use templates, you do not have to know much math. But you must know the language or the program intimately.
That means experience in using them. You must gain this for yourself, I cannot just hand it to you. You must practice with the commands and the help section that the program provides.2) The math is also something you learn by experience. You left in the middle of the help, I assume because you thought there was some shortcut way. I hoped you would find it so you could show me this shortcut, I have never found any shortcut way to learn math. I no longer believe there is one.
I understand, I know there is no short-cut but I got more grasp of some of the 3D math that is why I'm resurrecting it again
#189 Re: Help Me ! » Math Terms - Visually Described ? » 2010-12-20 04:16:04
Hi, I wanted to add to this thread what the following terms mean:
What are therules for adding, subtracting and dividing two 3x3 matrices ?
What is the difference between a 3x3 matrix and a 4x4 matrix ?
How do you convert a 3x3 matrix to X,Y,Z ?:)
#190 Coder's Corner » Help with jQuery » 2010-10-28 16:50:06
- SuperLynx
- Replies: 0
I hope someone can help me I'm trying create a custom jQuery script.
#191 Re: Help Me ! » Math Terms - Visually Described ? » 2010-08-30 08:32:43
I found a few web sites, I'm going to try to figure this out !
#192 Re: Help Me ! » Math Terms - Visually Described ? » 2010-08-28 11:33:40
If you had a 3x3 matrix where would it's centre point be?
#193 Re: Help Me ! » Math Terms - Visually Described ? » 2010-08-28 03:13:03
That is only one thing they can do. You can add 2 matrices or subtract or take the inverse or transpose
or take the determinant. Remember post #2. But yes matrix multiplication does the rotations around a central
point.
Basically you can add,subtract, multiply all the numbers within the matrix ? What do you mean that a matrix multiplication does the rotations around a central point ? What is the central point?
#194 Re: Help Me ! » Math Terms - Visually Described ? » 2010-08-28 02:12:11
If you want to understand something other than graphics and matrices then tell me now.
No, I don't.
A matrix 3 x 3 or 50 x 50 is just a rectangular grid of numbers. There is nothing magical about them. As I have said the rotation around the origin or any other point is done by multiplying 2 matrices they could be 2 x 2, 3 x 3 or more. Until we plot them the numbers have no meaning.
Oh that is what Matrix do is multiply one set of numbers within the matrix by another set.
23 45 12
84 91 2
14 4 16
#195 Re: Help Me ! » Math Terms - Visually Described ? » 2010-08-28 01:33:22
Can you at least try a different method for me to understand Matrix ? This method is not even slowly helping I have taken a look at those sites the information presented on those sites I knew how it worked.
#196 Re: Help Me ! » Math Terms - Visually Described ? » 2010-08-27 14:43:01
I want to understand 3x3 matrix but the plotting points on graphs isn't making me understand.
#197 Re: Help Me ! » Math Terms - Visually Described ? » 2010-08-27 10:01:48
That is helpful but specifically on Matrix, I'm understanding programming language codes as in Arrays, slowly but it's Matrix.
#198 Re: Help Me ! » Math Terms - Visually Described ? » 2010-08-27 08:50:11
I understand symmetry, theres gotta be a way I can understand where the light bulb goes off.
#199 Re: Help Me ! » Math Terms - Visually Described ? » 2010-08-27 07:53:53
That is helpful but do you have something like this for Matrix ?
#200 Re: Help Me ! » Math Terms - Visually Described ? » 2010-08-27 07:16:51
Can you explain to me without going though these graph sessions what Matrix can do ?