Find diagonal matrix $D$ such that $A D$ is Hurwitz
$begingroup$
Let $A in mathbb{R}^{m times m}$. Give necessary and/or sufficient conditions for the existence of a matrix $D in mathbb{R}^{m times m}$ such that all eigenvalues of $AD$ have negative real part (i.e., $AD$ Hurwitz). Some initial thoughts ...
Obviously $A, D$ must have full rank.
If $-A$ is so-called $D$-stable, the result seems to follow, although this is a much stronger condition than I need as it ensures that $AD$ is Hurwitz for all positive diagonal matrices $D$ (I think theres an easy extension there to allow for $D$ to have both positive and negative diagonal elements).
An equivalent formulation is that this is true if and only if there exists a $D$ and a matrix $P succ 0$ such that $P(AD)^{sf T} + (AD)P prec 0$. Letting $K = DP$ this is equivalent to the convex inequality $K^{sf T}A + AK prec 0$ in the variable $K$. If this is feasible for some $K^{star}$, you can then probably argue about the factorization $K^{star} = DP$ with $P succ 0$ and recover an appropriate choice of $D$?
Note: This matrix analysis question is motivated by a problem in systems and control theory.
matrices matrix-equations matrix-decomposition semidefinite-programming lmis
$endgroup$
add a comment |
$begingroup$
Let $A in mathbb{R}^{m times m}$. Give necessary and/or sufficient conditions for the existence of a matrix $D in mathbb{R}^{m times m}$ such that all eigenvalues of $AD$ have negative real part (i.e., $AD$ Hurwitz). Some initial thoughts ...
Obviously $A, D$ must have full rank.
If $-A$ is so-called $D$-stable, the result seems to follow, although this is a much stronger condition than I need as it ensures that $AD$ is Hurwitz for all positive diagonal matrices $D$ (I think theres an easy extension there to allow for $D$ to have both positive and negative diagonal elements).
An equivalent formulation is that this is true if and only if there exists a $D$ and a matrix $P succ 0$ such that $P(AD)^{sf T} + (AD)P prec 0$. Letting $K = DP$ this is equivalent to the convex inequality $K^{sf T}A + AK prec 0$ in the variable $K$. If this is feasible for some $K^{star}$, you can then probably argue about the factorization $K^{star} = DP$ with $P succ 0$ and recover an appropriate choice of $D$?
Note: This matrix analysis question is motivated by a problem in systems and control theory.
matrices matrix-equations matrix-decomposition semidefinite-programming lmis
$endgroup$
add a comment |
$begingroup$
Let $A in mathbb{R}^{m times m}$. Give necessary and/or sufficient conditions for the existence of a matrix $D in mathbb{R}^{m times m}$ such that all eigenvalues of $AD$ have negative real part (i.e., $AD$ Hurwitz). Some initial thoughts ...
Obviously $A, D$ must have full rank.
If $-A$ is so-called $D$-stable, the result seems to follow, although this is a much stronger condition than I need as it ensures that $AD$ is Hurwitz for all positive diagonal matrices $D$ (I think theres an easy extension there to allow for $D$ to have both positive and negative diagonal elements).
An equivalent formulation is that this is true if and only if there exists a $D$ and a matrix $P succ 0$ such that $P(AD)^{sf T} + (AD)P prec 0$. Letting $K = DP$ this is equivalent to the convex inequality $K^{sf T}A + AK prec 0$ in the variable $K$. If this is feasible for some $K^{star}$, you can then probably argue about the factorization $K^{star} = DP$ with $P succ 0$ and recover an appropriate choice of $D$?
Note: This matrix analysis question is motivated by a problem in systems and control theory.
matrices matrix-equations matrix-decomposition semidefinite-programming lmis
$endgroup$
Let $A in mathbb{R}^{m times m}$. Give necessary and/or sufficient conditions for the existence of a matrix $D in mathbb{R}^{m times m}$ such that all eigenvalues of $AD$ have negative real part (i.e., $AD$ Hurwitz). Some initial thoughts ...
Obviously $A, D$ must have full rank.
If $-A$ is so-called $D$-stable, the result seems to follow, although this is a much stronger condition than I need as it ensures that $AD$ is Hurwitz for all positive diagonal matrices $D$ (I think theres an easy extension there to allow for $D$ to have both positive and negative diagonal elements).
An equivalent formulation is that this is true if and only if there exists a $D$ and a matrix $P succ 0$ such that $P(AD)^{sf T} + (AD)P prec 0$. Letting $K = DP$ this is equivalent to the convex inequality $K^{sf T}A + AK prec 0$ in the variable $K$. If this is feasible for some $K^{star}$, you can then probably argue about the factorization $K^{star} = DP$ with $P succ 0$ and recover an appropriate choice of $D$?
Note: This matrix analysis question is motivated by a problem in systems and control theory.
matrices matrix-equations matrix-decomposition semidefinite-programming lmis
matrices matrix-equations matrix-decomposition semidefinite-programming lmis
edited Dec 25 '18 at 16:52
Rodrigo de Azevedo
13k41958
13k41958
asked Dec 25 '18 at 15:20
JohnJohn
1238
1238
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
Your problem is equivalent to the state feedback problem for LTI systems, so
$$
dot{x} = mathcal{A},x + mathcal{B},u
$$
with $u = -K,x$ such that $mathcal{A} - mathcal{B},K$ is Hurwitz. In your case $mathcal{A}=0$ and $mathcal{B} = -A$. When $mathcal{A}=0$ then the pair $(mathcal{A},mathcal{B})$ is stabilizable if and only if $mathcal{B}$ is full rank. The same conditions holds for your problem, so $A$ has to be full rank.
$endgroup$
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3052188%2ffind-diagonal-matrix-d-such-that-a-d-is-hurwitz%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Your problem is equivalent to the state feedback problem for LTI systems, so
$$
dot{x} = mathcal{A},x + mathcal{B},u
$$
with $u = -K,x$ such that $mathcal{A} - mathcal{B},K$ is Hurwitz. In your case $mathcal{A}=0$ and $mathcal{B} = -A$. When $mathcal{A}=0$ then the pair $(mathcal{A},mathcal{B})$ is stabilizable if and only if $mathcal{B}$ is full rank. The same conditions holds for your problem, so $A$ has to be full rank.
$endgroup$
add a comment |
$begingroup$
Your problem is equivalent to the state feedback problem for LTI systems, so
$$
dot{x} = mathcal{A},x + mathcal{B},u
$$
with $u = -K,x$ such that $mathcal{A} - mathcal{B},K$ is Hurwitz. In your case $mathcal{A}=0$ and $mathcal{B} = -A$. When $mathcal{A}=0$ then the pair $(mathcal{A},mathcal{B})$ is stabilizable if and only if $mathcal{B}$ is full rank. The same conditions holds for your problem, so $A$ has to be full rank.
$endgroup$
add a comment |
$begingroup$
Your problem is equivalent to the state feedback problem for LTI systems, so
$$
dot{x} = mathcal{A},x + mathcal{B},u
$$
with $u = -K,x$ such that $mathcal{A} - mathcal{B},K$ is Hurwitz. In your case $mathcal{A}=0$ and $mathcal{B} = -A$. When $mathcal{A}=0$ then the pair $(mathcal{A},mathcal{B})$ is stabilizable if and only if $mathcal{B}$ is full rank. The same conditions holds for your problem, so $A$ has to be full rank.
$endgroup$
Your problem is equivalent to the state feedback problem for LTI systems, so
$$
dot{x} = mathcal{A},x + mathcal{B},u
$$
with $u = -K,x$ such that $mathcal{A} - mathcal{B},K$ is Hurwitz. In your case $mathcal{A}=0$ and $mathcal{B} = -A$. When $mathcal{A}=0$ then the pair $(mathcal{A},mathcal{B})$ is stabilizable if and only if $mathcal{B}$ is full rank. The same conditions holds for your problem, so $A$ has to be full rank.
answered Dec 29 '18 at 15:15
Kwin van der VeenKwin van der Veen
5,4952828
5,4952828
add a comment |
add a comment |
Thanks for contributing an answer to Mathematics Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3052188%2ffind-diagonal-matrix-d-such-that-a-d-is-hurwitz%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown