Tagged Questions
1
vote
1answer
43 views
Matrix completion: supplementary questions
Continuation of the question here, what is going to happen if we change the some of the conditions. I write it as a quote from here and change the appropriate places which are underlined:
I need ...
1
vote
1answer
91 views
Matrix completion
I need to find an algorithm (if exists) of the following matrix completion problem.
I need to construct $n^2$ positive semi-definite matrices, say $\{P_i\}_{i=1}^n$. Entries of these matrices are ...
0
votes
0answers
48 views
Solving an overdetermined system of inequalities using null-space arguments
The solutions to a linear system of equations:
$$A\cdot x = b$$
(where $x$ is a $(n\times 1)$ column vector, $b$ is a $(m\times 1)$ column vector and $A$ is $(m\times n)$ matrix)
can all be ...
1
vote
1answer
142 views
Given two sets of vectors, how do I find a change of basis that will convert one set to another?
Given two sets of dimension $n$ vectors
$\lbrace v_1 , v_2 , \ldots , v_m \rbrace$, $\lbrace u_1, u_2, \ldots , u_m \rbrace$,
where $m > n$, is there a computational method (in particular, using ...
1
vote
0answers
83 views
Calculation of stopping condition for Conjugate Gradient
I am a person with programming background and need some math help.
I am looking at the source code for an implementation of the Conjugate Gradient iterative solver ...
0
votes
1answer
81 views
more matrix inversion
Related to a previous question: Suppose I want to invert a (sparse) matrix written in block form as
\begin{array}{cccc}
A_{11} & A_{12} & \ldots & A_{1n}\\
A_{21} & A_{22} & & ...
0
votes
2answers
98 views
efficient matrix inversion problem
So I'm trying to invert a matrix of the $\begin{pmatrix}
A & B \\
C & D
\end{pmatrix}$ where $A$ and $D$ are square, $D$ is much larger than $A$, and $D$ is diagonal. $A$ $B$ and $C$ have no ...
