bio  website  fph.altervista.org 

location  Pisa, Italy  
age  32  
visits  member for  5 years, 8 months 
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Numerical linear algebra. Mainly matrix equations and their applications (control theory, applied probability).
(This profile was written for Mathoverflow, but Stack Exchange insists on copying it over verbatim to other sites, where it makes less sense.)
1d

revised 
A question on the name of a property
toplevel tag 
1d

comment 
Determinant of block tridiagonal matrices
For the determinant it is probably the same. Determining rank and eigenvalues might require a bit more of algebraic machinery, though (nothing too fancy, extensions of finite fields). 
2d

answered  Deceptive linear algebra problem 
Jul 31 
comment 
Determinant of block tridiagonal matrices
If you are studying Lights Out, as you mentioned in the linked MSE thread, probably you should be interested in the determinant in $\mathbb{F}_2$, not in $\mathbb{R}$. 
Jul 20 
comment 
Can I find the gap between the two least eigenvalues of this special matrix A(t)?
@Toughee If the diagonal elements are completely arbitrary, I am afraid no. That's why I asked if you have a formula for them. Where do they come from? 
Jul 19 
revised 
Can I find the gap between the two least eigenvalues of this special matrix A(t)?
reference 
Jul 19 
answered  Can I find the gap between the two least eigenvalues of this special matrix A(t)? 
Jul 15 
reviewed  Approve powers of largest graded ideal of R contained in I 
Jul 15 
reviewed  Approve References on quaternionic geometry 
Jul 14 
reviewed  Approve teaching tag wiki excerpt 
Jul 14 
reviewed  Approve realanalysis tag wiki excerpt 
Jul 14 
reviewed  Approve realanalysis tag wiki 
Jul 12 
reviewed  Reject irreducibility of varieties defined by square roots equatiosn 
Jul 12 
reviewed  Approve Resource Constrained Routing with Refueling 
Jul 5 
reviewed  Approve Preimage of a maximal compact open subgroup in the simply connected cover 
Jul 5 
comment 
Worst case difference in rank by columnrow swapping
I am downvoting because you are not explaining yourself at all. Add an example! 
Jul 1 
reviewed  Approve A conjecture on the prime counting function 
Jun 25 
comment 
Can I find the gap between the two least eigenvalues of this special matrix A(t)?
Are all the values inside the band equal to $ct+d$, or can there be zeros also inside the band? 
Jun 25 
answered  Find inverse and determinant of a symmetric matrix  for a maximumlikelihood estimation 
Jun 23 
comment 
Prove or disprove a matrix logarithm equation
I am not a differential geometer, but after reading the formulation in your other question, I am more convinced that it can't be done, at least with a reasonably smooth function. What you ask for is a distancepreserving isomorphism between $\mathbb{S}^n_+$ and $\mathbb{R}^{n^2}$, and this shouldn't be possible because they have different curvature. 