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Inserting a Matrix into a Matrix on a TI89?

Unread postPosted: 23 Apr 2015, 04:00
by pikey
hello, I apologize that this is in english. I am using google translate to read this forum. I am having an issue that I hope that someone can help with. Is it possible to insert a matrix into a matrix. I will attempt to explain. I have a 3x3 matrix that I created named "a". I need to put "a" into a 2x2 matrix. Here is my attempt to show you what I mean:
{ [a] -[a] ]
[-[a] [a] ]

is it possible to do this on the TI89?
Thank you.

Re: Inserting a Matrix into a Matrix on a TI89?

Unread postPosted: 23 Apr 2015, 07:12
by Lionel Debroux
If I understand you correctly, you can't do what you want: more than two levels of lists (i.e. a list containing a matrix, or a matrix containing compound elements) are not supported on the TI-68k series.

Re: Inserting a Matrix into a Matrix on a TI89?

Unread postPosted: 23 Apr 2015, 07:18
by CVSoft
The TI-89 OS does not allow having a matrix nested in a matrix; the same rule applies to lists and vectors. Directly placing a matrix within a matrix is thus not an option; some other method will need to be used, and this will vary based on what you are trying to accomplish.

Re: Inserting a Matrix into a Matrix on a TI89?

Unread postPosted: 23 Apr 2015, 17:15
by Bisam
You may embed a matrix as a coefficient of another matrix... IF you convert it into a string before.
But of course, you will not be able to compute anything.

But I think you are trying to do block matrices computation... and it can be done using the fonction augment(m,p) which will append matrix p to matrix m (they must have the same number of lines).
The syntax augment(m;p) (note the ; instead of , ) stacks matrix m over p. It only exists on the most recent OSes... but I can't remember the first one to have it.
If it doesn't exist, you can use "transpose" to do it.

Re: Inserting a Matrix into a Matrix on a TI89?

Unread postPosted: 24 Apr 2015, 03:39
by pikey
Bisam wrote:You may embed a matrix as a coefficient of another matrix... IF you convert it into a string before.
But of course, you will not be able to compute anything.

But I think you are trying to do block matrices computation... and it can be done using the fonction augment(m,p) which will append matrix p to matrix m (they must have the same number of lines).
The syntax augment(m;p) (note the ; instead of , ) stacks matrix m over p. It only exists on the most recent OSes... but I can't remember the first one to have it.
If it doesn't exist, you can use "transpose" to do it.


thank you very much for your reply. I used MathLab to complete the necessary computation. I then attempted your method on mt ti89 and it worked whci will be very helpful for my exam next week. Thanks again

Re: Inserting a Matrix into a Matrix on a TI89?

Unread postPosted: 25 Apr 2015, 03:12
by compsystems
trick

[[a][b]
[c][d]] -> mat1

[[1][2]
[3][4]] -> mat2

[ e11=mat1, e12=mat2
e13=...., e14=... ]] -> mat3

[ [[a][b] , [[1][2]
[c][d]] [3][4]]
... , ... ]

Re: Inserting a Matrix into a Matrix on a TI89?

Unread postPosted: 25 Apr 2015, 03:29
by Adriweb
Humm yes, interesting trick :
Image

But it's not really a matrix inside, it's an expression (confirmed by getType)


By the way, TI themselves bend the rules with getVarInfo(), which produces a visual representation... but is an invalid matrix:
Image