adam W's user avatar
adam W's user avatar
adam W's user avatar
adam W
  • Member for 11 years, 2 months
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13 votes
7 answers
3k views

Is the square root of a triangular matrix necessarily triangular?

11 votes
2 answers
3k views

Is every square traceless matrix unitarily similar to a zero-diagonal matrix?

6 votes
1 answer
2k views

Characterizing a real symmetric matrix $A$ as $A = XX^T - YY^T$

5 votes
3 answers
497 views

$\Delta^d m^n =d! \sum_{k} \left[ m \atop k \right] { {k+n} \brace m + d}(-1)^{m+k}$ Is this a new formula?

4 votes
0 answers
120 views

Jacobi's Rotation has two possibilities, why do they both result in same upper triangular magnitude norm?

2 votes
0 answers
280 views

Parametric QR factorization: $\mathbf{D}(\alpha)\mathbf{V}^*$ a diagonal times a constant unitary matrix

1 vote
0 answers
84 views

Can this sum be shown to be zero? $\sum_k \left[ {m+1} \atop k \right]{ k+n \brace m}(-1)^{m+k} = 0$

1 vote
1 answer
71 views

There are $n!$ different unitary similarities that give $L_i \sim L_j$. Or are there more?

0 votes
1 answer
209 views

Factoring $\pm \Lambda$ from symmetric $A$ using $LDU$

-2 votes
4 answers
150 views

Complete instead of Complex, Irregular instead of Imaginary