forked from peterkty/drake
-
Notifications
You must be signed in to change notification settings - Fork 0
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
added LCP solver to thirdParty . working on joint limit example.
git-svn-id: https://svn.csail.mit.edu/locomotion/robotlib/trunk@3552 c9849af7-e679-4ec6-a44e-fc146a885bd3
- Loading branch information
russt
committed
Aug 17, 2012
1 parent
95f2b73
commit 4af540b
Showing
13 changed files
with
403 additions
and
25 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Binary file not shown.
Binary file not shown.
Binary file not shown.
Binary file not shown.
Binary file not shown.
Binary file not shown.
Binary file not shown.
Binary file not shown.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,172 @@ | ||
function [z,mu] = pathlcp(M,q,l,u,z,A,b,t,mu) | ||
% pathlcp(M,q,l,u,z,A,b,t,mu) | ||
% | ||
% Solve the standard linear complementarity problem using PATH: | ||
% z >= 0, Mz + q >= 0, z'*(Mz + q) = 0 | ||
% | ||
% Required input: | ||
% M(n,n) - matrix | ||
% q(n) - vector | ||
% | ||
% Output: | ||
% z(n) - solution | ||
% mu(m) - multipliers (if polyhedral constraints are present) | ||
% | ||
% Optional input: | ||
% l(n) - lower bounds default: zero | ||
% u(n) - upper bounds default: infinity | ||
% z(n) - starting point default: zero | ||
% A(m,n) - polyhedral constraint matrix default: empty | ||
% b(m) - polyhedral right-hand side default: empty | ||
% t(m) - type of polyhedral constraint default: 1 | ||
% < 0: less than or equal | ||
% 0: equation | ||
% > 0: greater than or equal | ||
% mu(m) - starting value for multipliers default: zero | ||
% | ||
% The optional lower and upper bounds are used to define a linear mixed | ||
% complementarity problem (box constrained variational inequality). | ||
% l <= z <= u | ||
% where l_i < z_i < u_i => (Mz + q)_i = 0 | ||
% l_i = z => (Mz + q)_i >= 0 | ||
% u_i = z => (Mz + q)_i <= 0 | ||
% | ||
% The optional constraints are used to define a polyhedrally constrained | ||
% variational inequality. These are transformed internally to a standard | ||
% mixed complementarity problem. The polyhedral constraints are of the | ||
% form | ||
% Ax ? b | ||
% where ? can be <=, =, or >= depending on the type specified for each | ||
% constraint. | ||
|
||
Big = 1e20; | ||
|
||
if (nargin < 2) | ||
error('two input arguments required for lcp(M, q)'); | ||
end | ||
|
||
if (~issparse(M)) | ||
M = sparse(M); % Make sure M is sparse | ||
end | ||
q = full(q(:)); % Make sure q is a column vector | ||
|
||
[mm,mn] = size(M); % Get the size of the inputs | ||
n = length(q); | ||
|
||
if (mm ~= mn | mm ~= n) | ||
error('dimensions of M and q must match'); | ||
end | ||
|
||
if (n == 0) | ||
error('empty model'); | ||
end | ||
|
||
if (nargin < 3 | isempty(l)) | ||
l = zeros(n,1); | ||
end | ||
|
||
if (nargin < 4 | isempty(u)) | ||
u = Big*ones(n,1); | ||
end | ||
|
||
if (nargin < 5 | isempty(z)) | ||
z = zeros(n,1); | ||
end | ||
|
||
z = full(z(:)); l = full(l(:)); u = full(u(:)); | ||
if (length(z) ~= n | length(l) ~= n | length(u) ~= n) | ||
error('Input arguments are of incompatible sizes'); | ||
end | ||
|
||
l = max(l,-Big*ones(n,1)); | ||
u = min(u,Big*ones(n,1)); | ||
z = min(max(z,l),u); | ||
|
||
m = 0; | ||
if (nargin > 5) | ||
if (nargin < 7) | ||
error('Polyhedral constraints require A and b'); | ||
end | ||
|
||
if (~issparse(A)) | ||
A = sparse(A); | ||
end | ||
b = full(b(:)); | ||
|
||
m = length(b); | ||
|
||
if (m > 0) | ||
|
||
[am, an] = size(A); | ||
|
||
if (am ~= m | an ~= n) | ||
error('Polyhedral constraints of incompatible sizes'); | ||
end | ||
|
||
if (nargin < 8 | isempty(t)) | ||
t = ones(m,1); | ||
end | ||
|
||
if (nargin < 9 | isempty(mu)) | ||
mu = zeros(m,1); | ||
end | ||
|
||
t = full(t(:)); mu = full(mu(:)); | ||
if (length(t) ~= m | length(mu) ~= m) | ||
error('Polyhedral input arguments are of incompatible sizes'); | ||
end | ||
|
||
l_p = -Big*ones(m,1); | ||
u_p = Big*ones(m,1); | ||
|
||
idx = find(t > 0); | ||
if (length(idx) > 0) | ||
l_p(idx) = zeros(length(idx),1); | ||
end | ||
|
||
idx = find(t < 0); | ||
if (length(idx) > 0) | ||
u_p(idx) = zeros(length(idx),1); | ||
end | ||
|
||
mu = min(max(mu,l_p),u_p); | ||
|
||
M = [M -A'; A sparse(m,m)]; | ||
q = [q; -b]; | ||
|
||
z = [z; mu]; | ||
l = [l; l_p]; | ||
u = [u; u_p]; | ||
else | ||
if (nargin >= 9 & ~isempty(mu)) | ||
error('No polyhedral constraints -- multipliers set.'); | ||
end | ||
|
||
if (nargin >= 8 & ~isempty(t)) | ||
error('No polyhedral constraints -- equation types set.'); | ||
end | ||
end | ||
end | ||
|
||
idx = find(l > u); | ||
if length(idx) > 0 | ||
error('Bounds infeasible.'); | ||
end | ||
|
||
nnzJ = nnz(M); | ||
|
||
[status, ttime] = lcppath(n+m, nnzJ, z, l, u, M, q); | ||
|
||
if (status ~= 1) | ||
status, | ||
error('Path fails to solve problem'); | ||
end | ||
|
||
mu = []; | ||
if (m > 0) | ||
mu = z(n+1:n+m); | ||
z = z(1:n); | ||
end | ||
|
||
return; | ||
|
Oops, something went wrong.