Dynamic-Calibration/utils/YALMIP-master/@sdpvar/max.m

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2019-12-18 11:25:45 +00:00
function [y,loc] = max(varargin)
%MAX (overloaded)
%
% t = max(X)
% t = max(X,Y)
% t = max(X,[],DIM)
%
% Creates an internal structure relating the variable t with convex
% operator max(X).
%
% The variable t is primarily meant to be used in convexity preserving
% operations such as t<=..., minimize t etc.
%
% If the variable is used in a non-convexity preserving operation, such as
% t>=0, a mixed integer model will be derived.
%
% See built-in MAX for syntax.
% To simplify code flow, code for different #output/inputs
if nargout == 2
[y,loc] = max_with_loc(varargin{:});
return
end
switch nargin
case 1
% Four cases:
% 1. One scalar input, return same as output
% 2. A vector input should give scalar output
% 3. Matrix input returns vector output
% 4. User wants location index
X = varargin{1};
if max(size(X))==1
y = X;
return
elseif min(size(X))==1
X = removeInf(X);
if numel(X) == 0
y = -inf;
elseif isnumeric(X)
y = max(X);
elseif length(X) == 1
y = X;
else
y = yalmip('define','max_internal',X);
% Some special code to ensure max(x) when x is a simple
% binary vector yields a binary graph variable. This will
% simplify some models
reDeclareForBinaryMax(y,X);
end
return
else
% This is just short-hand for general command
y = max(X,[],1);
end
case 2
X = varargin{1};
Y = varargin{2};
[nx,mx] = size(X);
[ny,my] = size(Y);
if ~((nx*mx==1) | (ny*my==1))
% No scalar, so they have to match
if ~((nx==ny) & (mx==my))
error('Array dimensions must match.');
end
end
% Convert to compatible matrices
if nx*mx==1
X = X*ones(ny,my);
nx = ny;
mx = my;
elseif ny*my == 1
Y = Y*ones(nx,mx);
ny = nx;
my = mx;
end
% Ok, done with error checks etc.
Z = [reshape(X,1,[]);reshape(Y,1,[])];
y = yalmip('define','max_internal',Z);
reDeclareForBinaryMax(y,Z);
y = reshape(y,nx,mx);
case 3
X = varargin{1};
Y = varargin{2};
DIM = varargin{3};
if ~(isa(X,'sdpvar') & isempty(Y))
error('MAX with two matrices to compare and a working dimension is not supported.');
end
if ~isa(DIM,'double')
error('Dimension argument must be 1 or 2.');
end
if ~(length(DIM)==1)
error('Dimension argument must be 1 or 2.');
end
if ~(DIM==1 | DIM==2)
error('Dimension argument must be 1 or 2.');
end
if DIM==1
% Create one extended variable per column
y = [];
for i = 1:size(X,2)
inparg = extsubsref(X,1:size(X,1),i);
if isa(inparg,'sdpvar')
inparg = removeInf(inparg);
if numel(inparg)==0
y = [y -inf];
elseif isnumeric(inparg)
y = [y max(inparg)];
elseif length(inparg) == 1
y = [y max(inparg)];
else
z = yalmip('define','max_internal',inparg);
y = [y z];
% Some special code to ensure max(x) when x is a simple
% binary vector yields a binary graph variable. This will
% improve some models
reDeclareForBinaryMax(z,inparg);
end
else
y = [y max(inparg)];
end
end
else
% Re-use code recursively
y = max(X',[],1)';
end
otherwise
error('Too many input arguments.');
end
function X = removeInf(X)
Xbase = getbase(X);
infs = find( isinf(Xbase(:,1)) & (Xbase(:,1)<0));
if ~isempty(infs)
X.basis(infs,:) = [];
if X.dim(1)>X.dim(2)
X.dim(1) = X.dim(1) - length(infs);
else
X.dim(2) = X.dim(2) - length(infs);
end
end
infs = find(isinf(Xbase(:,1)) & (Xbase(:,1)>0));
if ~isempty(infs)
X = inf;
end