37 lines
841 B
Mathematica
37 lines
841 B
Mathematica
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function varargout = tan (varargin)
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%TAN (overloaded)
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switch class(varargin{1})
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case 'double'
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error('Overloaded SDPVAR/TAN CALLED WITH DOUBLE. Report error')
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case 'sdpvar'
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varargout{1} = InstantiateElementWise(mfilename,varargin{:});
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case 'char'
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operator = struct('convexity','none','monotonicity','none','definiteness','none','model','callback');
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operator.convexhull = [];
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operator.bounds = @bounds;
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operator.derivative = @(x)(sec(x).^2);
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varargout{1} = [];
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varargout{2} = operator;
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varargout{3} = varargin{3};
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otherwise
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error('SDPVAR/TAN called with CHAR argument?');
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end
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function [L,U] = bounds(xL,xU)
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n1 = fix((xL+pi/2)/(pi));
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n2 = fix((xU+pi/2)/(pi));
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if n1==n2
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L = tan(xL);
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U = tan(xU);
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else
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L = -inf;
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U = inf;
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end
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