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Yes, I can normalize a vector but what did you need it for?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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What does Normalize do ?
What are 4x4 matrices, and I assume their is determinants within a 4x4 correct ?
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Normalizing a vector means turning it into a vector with the same direction but a length of 1.
A 4x4 matrix is a matrix with 4 rows and 4 columns. So it has 16 elements.
It is always possible to take the determinant of any square matrix. It is computationally difficult by the standard human methods.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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How do you figure out a determinant ???
Normalizing a vectors just means make it always a length of 1 ?
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That is all it means. Its magnitude is 1 yes.
What size are you after? As I said 2 x 2 easy. 3 x 3 hard. 4 x 4 impossible with pencil and paper. Your programming language is similar to Matlab you said. Surely, you have command for it.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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How do I figure out the determinant for a 3x3 what do the extra rows & columns in 4x4 represent?
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Hi SuperLynx;
That would depend. In 3D work they use a 4 x 4 for convenience I think. Mathematically only a 3 x 3 is necessary. This I showed you earlier how to rotate, translate and dilate points on a 2D screen. Anything can go into an n x n matrix.
If you now think you can answer this:
3* y - 12 if I plug in 17 into y.
Then I will show you a formula for a 3 x 3 determinant, okay?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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If you now think you can answer this:
3* y - 12 if I plug in 17 into y.
Then I will show you a formula for a 3 x 3 determinant, okay?
39???
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Are you sure?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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Yes I'm sure !
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Okay. you asked for it, you get it.
Now you told me you can handle this. That is how the guy on that site is getting the determinant.
Now do you want to see how to get a determinant of a real live matrix? If I give you one can you get it?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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Lynx, what exactly are you asking for?
MATH......that is all.
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I don't understand how you figured out the determinant ? It appears that you are grabbing random letters in the matrix then doing the formula, I know you're not so what are you doing ?
Now do you want to see how to get a determinant of a real live matrix? If I give you one can you get it?
Yes !
Lynx, what exactly are you asking for?
I'm figuring out advanced math piece by piece ! To relate it to an application I use regularly.
Last edited by SuperLynx (2011-01-22 14:05:56)
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Forget about the derivation. It is not important, I do not know it off hand. It is the formula that counts.
Can you find the determinant?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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Is there a rule for finding it ?
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Yes I have given you the rule. So, do you need help on that determinant because all you have to do is plug into the formula on the bottom.
This is the rule:
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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Hi SuperLynx,
You can do it by using the recursive definition for determinants.
E.g. consider a 3X3 determinant
That is, you take out the first element of the first row, delete the row and column where it lies, and then compute the determinant of the elements which remain.
Then take out the second element of the first row, prefix a minus sign, delete the row and column where it lies, and then compute the determinant of the elements which remain.
Then take out the third element of the first row, prefix a plus sign, delete the row and column where it lies, and then compute the determinant of the elements which remain.
Utimately, we end up in 2X2 determinant, which is easy to compute.
If there are more rows and columns, you compute it in the same way, with alternate plus and minus.
Go here to know some theorems and examples: http://www.numbertheory.org/book/cha4.pdf
Last edited by gAr (2011-01-22 15:51:45)
"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense" - Buddha?
"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."
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I'm not following... !
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He just showed you how to do it using minors but you do not know how to do a 2 x 2 so you are stuck using the formula. The rule as you call it.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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Hi SuperLynx,
Did you check the document : http://www.numbertheory.org/book/cha4.pdf
I don't know to explain better
Tell what you did not follow.
"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense" - Buddha?
"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."
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This is for a 3x3 matrix, correct ?
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Hi Superlynx,
What you've done is wrong.. It's not putting numbers together rather its multiplication..
1x5x9-1x6x8-2x4x9+2x6x7+3x4x8-3x5x7.. and the answer is zero..
I come from a civilization which has given the world the number 0..
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?
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Hi SuperLynx,
Did you follow?
"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense" - Buddha?
"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."
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