Thread: Fractional Powers of a Matrix

Hi everyone ,
I want to calculate fractional power of a matrix. How i will do it ? Is there any library related to matrix in c or c++?

with regards
bibhu .

Yes there is and it's on sale this week for only $1500.00...

Alternatively you could sit down and actually read up on arrays and figure out the 30 or so lines of code it would take for yourself.

When handed a challenge don't go chasing libraries or prefabricated code... THINK about the task until you understand it, work out a solution, write the code, test the program... a very simple 4 step process.

So, get started on this by yourself. Get your code as far along as you can. If you run into trouble post your code here --using code tags-- and we'll see what we can do.

Homework Policy

thanks for reply.
Can you tell me how to start ?
If the power is an integer the i may try to multiply the matrix that much of time but it is a fraction.So can you tell any algorithm so that i can start.

What, you can't multiply fractions?

Look it's all just numbers... why is this any harder than integers?
Just make a matrix of float... as in float array[10][10] instead of int array[10][10]... load your matrix, then treat the numbers as numbers...

Work the problem as I described... THINK, PLAN, DO, TEST... Don't be expecting us to do it for you.

Actually my power is in fraction means if A is a matrix then i have to calculate A^0.5

Ok... one more time... Get started on your own. Work the problem, don't beg for libraries and code... THINK it through.

If it's the math that has you stymied, try a math forum...

If you get stuck on the code, post what you've got and we'll try to help...
This board's policies do not let us post "canned" code.

Hi, bibhukalyana.

If you don't feel like figuring it out, you could take a look at a program called MATLAB, which is an amazing tool for dealing with matrices.

However, if you do want to figure it out, commontater (despite what could be misunderstood as rudeness, he's just tired of people coming to the board trying to get their problems solved without any effort)
provides great outline in implementing code (in fact in all of problem solving):

1) Find out the purpose of the problem (you're done that)
2) Find the resources you will need to solve the problem
3) Implement your solution
4) Test and improve.

I have just started learning matrices and I have just started learning programming so even if I wanted to help, I wouldn't be able to without spending too much time.
So, best of luck.

As mentioned, you're going to have to first discover how to find powers of a matrix. Interestingly, it doesn't involve multiplying matrices together a bunch of times.

Matrix (mathematics) - Wikipedia, the free encyclopedia

Originally Posted by tabstop

As mentioned, you're going to have to first discover how to find powers of a matrix. Interestingly, it doesn't involve multiplying matrices together a bunch of times.

Matrix (mathematics) - Wikipedia, the free encyclopedia

It really doesn't lol.
As far as I've researched on the internet, it is not possible to find fractional exponent of a matrix. But then, internet could be wrong.
I'm really interested in commontater's solution in this because he said it only requires around 30 lines.
That's beastly right there lol.
I can't even code within 30 lines reducing the matrix in an echelon form lolll

Originally Posted by kpark91

It really doesn't lol.
As far as I've researched on the internet, it is not possible to find fractional exponent of a matrix. But then, internet could be wrong.

The link I posted shows how to find the fractional exponent of a matrix.

I've looked at it...
Where is it?
All I see that is related to exponenet is
An = (VDV−1)n = VDV−1VDV−1...VDV−1 = VDnV−1

Do you mean if you want to find A^(n/m), you should first perform A^n (B) and then B^(1/m) ???

Sorry for so many questions.
I read the whole article (more like reading it to find the word fraction since I'm having some trouble understanding the theories lol) and I can't seem to find it O_o

That's the one. D is just a diagonal matrix, so raising it to a power means you just put the power on the numbers on the diagonal.

Originally Posted by tabstop

That's the one. D is just a diagonal matrix, so raising it to a power means you just put the power on the numbers on the diagonal.

Ahhh I remember noww haha;;

Thank you!

sounds like I really need to review my lin.alg. before I head back to school O_o