lightpathPathComputation.m

% lightpathPathComputation
% 
%>> Usage: [sequenceOfNodeIDs , sequenceOfFiberIDs , sequenceOfWavelengthIDs] =...
%     lightpathPathComputation (lpID , phys, netState)
%
%>> Abstract: This function computes the path of a lightpath from the
%   network state, the physical topology and the lightpath ID .
%
%>> Arguments:
% o  In: 
%  . lpID: Identifier number of the lightpath.
%
%  . netState: NetState Structure. More information about netState in
%    section "Structure of netState variable" from Help. 
%
%  . phys: Phys Structure. More information about netState in section 
%    "Structure of phys variable" from Help.
%
% o Out:
%   . sequenceOfNodeIDs: Row vector with the sorted sequence of IDs of
%     the nodes which the lightpath consist of.
%    sequenceOfFiberIDs: Row vector with the sorted sequence of IDs of
%     the links which the lightpath consist of.
%   . sequenceOfWavelengthIDs: Row vector with the sorted sequence of
%     wavelength IDs used in each link which the lightpath consist of.

function [sequenceOfNodeIDs , sequenceOfFiberIDs , sequenceOfWavelengthIDs] =...
    lightpathPathComputation (lpID , phys, netState)

if (nargin==0),  help lightpathPathComputation;return, end %help calling
if (nargin~=3),  error('1: Incorrect number of arguments.'),end %Number of input arguments different of 3

%This function calculate the path of a lightpath from the network state and
%the lightpath ID .

currentNode = netState.lightpathTable (lpID,2);
egressNode = netState.lightpathTable (lpID,3);

mixedSequenceOfLinks=find(netState.lightpathRoutingMatrix (lpID,:)~=0);
mixedSequenceOfLinksTable=phys.linkTable(mixedSequenceOfLinks,1:2);
sequenceOfNodeIDs = currentNode;
sequenceOfFiberIDs = [];
sequenceOfWavelengthIDs = [];

while currentNode ~= egressNode 
    linkID=mixedSequenceOfLinks (find(currentNode==mixedSequenceOfLinksTable(:,1)));
    nextNode = phys.linkTable (linkID,2);
    sequenceOfNodeIDs = [sequenceOfNodeIDs nextNode]; 
    sequenceOfFiberIDs = [sequenceOfFiberIDs linkID];
    sequenceOfWavelengthIDs = [sequenceOfWavelengthIDs netState.lightpathRoutingMatrix(lpID,linkID)];
    currentNode = nextNode;
end