Take the 2-minute tour ×
Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. It's 100% free, no registration required.

Which topic(s) does this matrix come from? What is the name of this matrix?

$$\pmatrix{1&1&1\\1&\omega&\omega^2\\1&\omega^2&\omega}$$

share|improve this question
10  
That's a Vandermonde matrix, as well as the matrix of the discrete Fourier transform of size $3$... It is not quite clear what the purpose of this question is, though! –  Mariano Suárez-Alvarez Feb 10 '12 at 5:28
1  
We are assuming that $\omega$ here is a root of unity, of course (too bad OP did not define his/her notation)... if not, then it's just some symmetric matrix. –  J. M. Feb 10 '12 at 5:44

1 Answer 1

This is the discrete Fourier transform matrix of size $3$. It naturally appears mathematically in the representation theory (don't be intimidated by this!) of the cyclic groups $\mathbb{Z}/n\mathbb{Z}$, as well as practically in signal processing and related fields.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.