Linear Algebra Sucks, help me cheat by finding a matrix program

[Babbler]

I am taking linear algebra, and the computations aren't difficult or tedious to me, or, at least, not now (we're now at the beginning of Gauss-Jordan method). Our college uses Maple, which I could have gotten for free from my Cal-I teacher, but never got around to it. Beside, neither my cal-II and linear algebra professors were tech heads.

But you don't need a fancy computer program or even a graphing calculator -- my scientific calculator (Sharp EL-546W) has a matrix mode. I just don't know how it work.

 

[Rem]

My TI-83 Plus has a wide variety of matrix solving algorithms. It can:

-Multiply Matrices
-Find Inverse Matrices
-Find Determinates
-Row Reduce/Gaussian Elimination

So, if the TI-83 does this and more, with no problem your TI-89 should as well.

 

[The Last Conformist]

I got MatLab for $6, Which reminds me I should be installing it again.

 

[Aphex_Twin]

Google search "eigenmath".
It's quite small (700 kb) and powerful. But if you just want matrix multiplication, the basic scheme is:

for i = 0 to m-1:
    for j = 0 to n-1:
        for k = 0 to p-1:
            c[ i ][ j ] += a[ i ][ k ] * b[ k ][ j ]

where a is an [m x n] matrix, b is [n x p] and c is [m x p]

 

[ArbitraryGuy]

There's a free MatLab "clone" called SciLab. I used it for my linear algebra class - it's pretty handy (and free). http://www.scilab.org/

 

[Aphex_Twin]

Or you can try Axiom or Yacas (free and quite powerful CAS)...

 

[newfangle]

Oh for God sakes just compute it by hand.

Multiple 4x4ish matrices takes no longer than inputing the revelent entry-wise values into a program.

 

[luiz]

Matlab is indeed the solution to all your problems.
Expensive? I bought it for 4 USD...

 

[newfangle]

That would be the price of the blank CDs?

 

[Yom]

Speaking of Linear Algebra, my professor kind of sucks. He teaches to us like we're ********, so we haven't even started using the book yet, which makes getting an A easy, but I still want to know all the information. Plus, with grade deflation in place this year, the difference between an A and a B could be the difference between an A+ and a regular A (or A-).

 

[newfangle]

What material is he teaching?

Keep in mind that many math professors try to reduce the damage that high school does to math comprehension.

For instance, some people actually believe sqrt(25) can equal -5. That sort of blasphemy has to be weeded out to ensure a nice basis of non-retardation is in place for higher level topics.

 

[nihilistic]

Not sure if this should be in OT or Computer Talk...

I'm sick of doing all these dang matrix problems in my homework sets. Find me a free program that will matrix operations so I don't have to waste my time doing things I already have had drilled firmly into my head.

The TI89 certainly does the basic functions such as reduced row echelon form, eigenvector, eigenvalue, inverse, etc. the more advanced stuff such as the decompositions (LU, SVD, Cholesky, eigen, jordan, ...) I doubt it has. You could look at the add-ons on http://www.ticalc.org/ and/or download the virtual ti program and test stuff out on your computer.

Or you can just get something like mathematica. Out of the computer programs that does this kind of thing, (assuming you are doing this for a math class) mathematica is the best. If you are doing physics matlab is better.

 

[luiz]

That would be the price of the blank CDs?

Nah, a blank CD costs less then 1 USD over here.
But since I'm to lazy to crack programs myself, I bought an all-done copy in the lawless territory known as Uruguaiana.