--- /dev/null
+%# Copyright (C) 2008-2012, Thomas Treichl <treichl@users.sourceforge.net>
+%# OdePkg - A package for solving ordinary differential equations and more
+%#
+%# This program is free software; you can redistribute it and/or modify
+%# it under the terms of the GNU General Public License as published by
+%# the Free Software Foundation; either version 2 of the License, or
+%# (at your option) any later version.
+%#
+%# This program is distributed in the hope that it will be useful,
+%# but WITHOUT ANY WARRANTY; without even the implied warranty of
+%# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+%# GNU General Public License for more details.
+%#
+%# You should have received a copy of the GNU General Public License
+%# along with this program; If not, see <http://www.gnu.org/licenses/>.
+
+%# -*- texinfo -*-
+%# @deftypefn {Function File} {[@var{}] =} ode78d (@var{@@fun}, @var{slot}, @var{init}, @var{lags}, @var{hist}, [@var{opt}], [@var{par1}, @var{par2}, @dots{}])
+%# @deftypefnx {Command} {[@var{sol}] =} ode78d (@var{@@fun}, @var{slot}, @var{init}, @var{lags}, @var{hist}, [@var{opt}], [@var{par1}, @var{par2}, @dots{}])
+%# @deftypefnx {Command} {[@var{t}, @var{y}, [@var{xe}, @var{ye}, @var{ie}]] =} ode78d (@var{@@fun}, @var{slot}, @var{init}, @var{lags}, @var{hist}, [@var{opt}], [@var{par1}, @var{par2}, @dots{}])
+%#
+%# This function file can be used to solve a set of non--stiff delay differential equations (non--stiff DDEs) with a modified version of the well known explicit Runge--Kutta method of order (7,8).
+%#
+%# If this function is called with no return argument then plot the solution over time in a figure window while solving the set of DDEs that are defined in a function and specified by the function handle @var{@@fun}. The second input argument @var{slot} is a double vector that defines the time slot, @var{init} is a double vector that defines the initial values of the states, @var{lags} is a double vector that describes the lags of time, @var{hist} is a double matrix and describes the history of the DDEs, @var{opt} can optionally be a structure array that keeps the options created with the command @command{odeset} and @var{par1}, @var{par2}, @dots{} can optionally be other input arguments of any type that have to be passed to the function defined by @var{@@fun}.
+%#
+%# In other words, this function will solve a problem of the form
+%# @example
+%# dy/dt = fun (t, y(t), y(t-lags(1), y(t-lags(2), @dots{})))
+%# y(slot(1)) = init
+%# y(slot(1)-lags(1)) = hist(1), y(slot(1)-lags(2)) = hist(2), @dots{}
+%# @end example
+%#
+%# If this function is called with one return argument then return the solution @var{sol} of type structure array after solving the set of DDEs. The solution @var{sol} has the fields @var{x} of type double column vector for the steps chosen by the solver, @var{y} of type double column vector for the solutions at each time step of @var{x}, @var{solver} of type string for the solver name and optionally the extended time stamp information @var{xe}, the extended solution information @var{ye} and the extended index information @var{ie} all of type double column vector that keep the informations of the event function if an event function handle is set in the option argument @var{opt}.
+%#
+%# If this function is called with more than one return argument then return the time stamps @var{t}, the solution values @var{y} and optionally the extended time stamp information @var{xe}, the extended solution information @var{ye} and the extended index information @var{ie} all of type double column vector.
+%#
+%# For example:
+%# @itemize @minus
+%# @item
+%# the following code solves an anonymous implementation of a chaotic behavior
+%#
+%# @example
+%# fcao = @@(vt, vy, vz) [2 * vz / (1 + vz^9.65) - vy];
+%#
+%# vopt = odeset ("NormControl", "on", "RelTol", 1e-3);
+%# vsol = ode78d (fcao, [0, 100], 0.5, 2, 0.5, vopt);
+%#
+%# vlag = interp1 (vsol.x, vsol.y, vsol.x - 2);
+%# plot (vsol.y, vlag); legend ("fcao (t,y,z)");
+%# @end example
+%#
+%# @item
+%# to solve the following problem with two delayed state variables
+%#
+%# @example
+%# d y1(t)/dt = -y1(t)
+%# d y2(t)/dt = -y2(t) + y1(t-5)
+%# d y3(t)/dt = -y3(t) + y2(t-10)*y1(t-10)
+%# @end example
+%#
+%# one might do the following
+%#
+%# @example
+%# function f = fun (t, y, yd)
+%# f(1) = -y(1); %% y1' = -y1(t)
+%# f(2) = -y(2) + yd(1,1); %% y2' = -y2(t) + y1(t-lags(1))
+%# f(3) = -y(3) + yd(2,2)*yd(1,2); %% y3' = -y3(t) + y2(t-lags(2))*y1(t-lags(2))
+%# endfunction
+%# T = [0,20]
+%# res = ode78d (@@fun, T, [1;1;1], [5, 10], ones (3,2));
+%# @end example
+%#
+%# @end itemize
+%# @end deftypefn
+%#
+%# @seealso{odepkg}
+
+function [varargout] = ode78d (vfun, vslot, vinit, vlags, vhist, varargin)
+
+ if (nargin == 0) %# Check number and types of all input arguments
+ help ('ode78d');
+ error ('OdePkg:InvalidArgument', ...
+ 'Number of input arguments must be greater than zero');
+
+ elseif (nargin < 5)
+ print_usage;
+
+ elseif (~isa (vfun, 'function_handle'))
+ error ('OdePkg:InvalidArgument', ...
+ 'First input argument must be a valid function handle');
+
+ elseif (~isvector (vslot) || length (vslot) < 2)
+ error ('OdePkg:InvalidArgument', ...
+ 'Second input argument must be a valid vector');
+
+ elseif (~isvector (vinit) || ~isnumeric (vinit))
+ error ('OdePkg:InvalidArgument', ...
+ 'Third input argument must be a valid numerical value');
+
+ elseif (~isvector (vlags) || ~isnumeric (vlags))
+ error ('OdePkg:InvalidArgument', ...
+ 'Fourth input argument must be a valid numerical value');
+
+ elseif ~(isnumeric (vhist) || isa (vhist, 'function_handle'))
+ error ('OdePkg:InvalidArgument', ...
+ 'Fifth input argument must either be numeric or a function handle');
+
+ elseif (nargin >= 6)
+
+ if (~isstruct (varargin{1}))
+ %# varargin{1:len} are parameters for vfun
+ vodeoptions = odeset;
+ vfunarguments = varargin;
+
+ elseif (length (varargin) > 1)
+ %# varargin{1} is an OdePkg options structure vopt
+ vodeoptions = odepkg_structure_check (varargin{1}, 'ode78d');
+ vfunarguments = {varargin{2:length(varargin)}};
+
+ else %# if (isstruct (varargin{1}))
+ vodeoptions = odepkg_structure_check (varargin{1}, 'ode78d');
+ vfunarguments = {};
+
+ end
+
+ else %# if (nargin == 5)
+ vodeoptions = odeset;
+ vfunarguments = {};
+ end
+
+ %# Start preprocessing, have a look which options have been set in
+ %# vodeoptions. Check if an invalid or unused option has been set and
+ %# print warnings.
+ vslot = vslot(:)'; %# Create a row vector
+ vinit = vinit(:)'; %# Create a row vector
+ vlags = vlags(:)'; %# Create a row vector
+
+ %# Check if the user has given fixed points of time
+ if (length (vslot) > 2), vstepsizegiven = true; %# Step size checking
+ else vstepsizegiven = false; end
+
+ %# Get the default options that can be set with 'odeset' temporarily
+ vodetemp = odeset;
+
+ %# Implementation of the option RelTol has been finished. This option
+ %# can be set by the user to another value than default value.
+ if (isempty (vodeoptions.RelTol) && ~vstepsizegiven)
+ vodeoptions.RelTol = 1e-6;
+ warning ('OdePkg:InvalidOption', ...
+ 'Option "RelTol" not set, new value %f is used', vodeoptions.RelTol);
+ elseif (~isempty (vodeoptions.RelTol) && vstepsizegiven)
+ warning ('OdePkg:InvalidOption', ...
+ 'Option "RelTol" will be ignored if fixed time stamps are given');
+ %# This implementation has been added to odepkg_structure_check.m
+ %# elseif (~isscalar (vodeoptions.RelTol) && ~vstepsizegiven)
+ %# error ('OdePkg:InvalidOption', ...
+ %# 'Option "RelTol" must be set to a scalar value for this solver');
+ end
+
+ %# Implementation of the option AbsTol has been finished. This option
+ %# can be set by the user to another value than default value.
+ if (isempty (vodeoptions.AbsTol) && ~vstepsizegiven)
+ vodeoptions.AbsTol = 1e-6;
+ warning ('OdePkg:InvalidOption', ...
+ 'Option "AbsTol" not set, new value %f is used', vodeoptions.AbsTol);
+ elseif (~isempty (vodeoptions.AbsTol) && vstepsizegiven)
+ warning ('OdePkg:InvalidOption', ...
+ 'Option "AbsTol" will be ignored if fixed time stamps are given');
+ else %# create column vector
+ vodeoptions.AbsTol = vodeoptions.AbsTol(:);
+ end
+
+ %# Implementation of the option NormControl has been finished. This
+ %# option can be set by the user to another value than default value.
+ if (strcmp (vodeoptions.NormControl, 'on')), vnormcontrol = true;
+ else vnormcontrol = false;
+ end
+
+ %# Implementation of the option NonNegative has been finished. This
+ %# option can be set by the user to another value than default value.
+ if (~isempty (vodeoptions.NonNegative))
+ if (isempty (vodeoptions.Mass)), vhavenonnegative = true;
+ else
+ vhavenonnegative = false;
+ warning ('OdePkg:InvalidOption', ...
+ 'Option "NonNegative" will be ignored if mass matrix is set');
+ end
+ else vhavenonnegative = false;
+ end
+
+ %# Implementation of the option OutputFcn has been finished. This
+ %# option can be set by the user to another value than default value.
+ if (isempty (vodeoptions.OutputFcn) && nargout == 0)
+ vodeoptions.OutputFcn = @odeplot;
+ vhaveoutputfunction = true;
+ elseif (isempty (vodeoptions.OutputFcn)), vhaveoutputfunction = false;
+ else vhaveoutputfunction = true;
+ end
+
+ %# Implementation of the option OutputSel has been finished. This
+ %# option can be set by the user to another value than default value.
+ if (~isempty (vodeoptions.OutputSel)), vhaveoutputselection = true;
+ else vhaveoutputselection = false; end
+
+ %# Implementation of the option Refine has been finished. This option
+ %# can be set by the user to another value than default value.
+ if (isequal (vodeoptions.Refine, vodetemp.Refine)), vhaverefine = true;
+ else vhaverefine = false; end
+
+ %# Implementation of the option Stats has been finished. This option
+ %# can be set by the user to another value than default value.
+
+ %# Implementation of the option InitialStep has been finished. This
+ %# option can be set by the user to another value than default value.
+ if (isempty (vodeoptions.InitialStep) && ~vstepsizegiven)
+ vodeoptions.InitialStep = abs (vslot(1,1) - vslot(1,2)) / 10;
+ vodeoptions.InitialStep = vodeoptions.InitialStep / 10^vodeoptions.Refine;
+ warning ('OdePkg:InvalidOption', ...
+ 'Option "InitialStep" not set, new value %f is used', vodeoptions.InitialStep);
+ end
+
+ %# Implementation of the option MaxStep has been finished. This option
+ %# can be set by the user to another value than default value.
+ if (isempty (vodeoptions.MaxStep) && ~vstepsizegiven)
+ vodeoptions.MaxStep = abs (vslot(1,1) - vslot(1,length (vslot))) / 10;
+ %# vodeoptions.MaxStep = vodeoptions.MaxStep / 10^vodeoptions.Refine;
+ warning ('OdePkg:InvalidOption', ...
+ 'Option "MaxStep" not set, new value %f is used', vodeoptions.MaxStep);
+ end
+
+ %# Implementation of the option Events has been finished. This option
+ %# can be set by the user to another value than default value.
+ if (~isempty (vodeoptions.Events)), vhaveeventfunction = true;
+ else vhaveeventfunction = false; end
+
+ %# The options 'Jacobian', 'JPattern' and 'Vectorized' will be ignored
+ %# by this solver because this solver uses an explicit Runge-Kutta
+ %# method and therefore no Jacobian calculation is necessary
+ if (~isequal (vodeoptions.Jacobian, vodetemp.Jacobian))
+ warning ('OdePkg:InvalidOption', ...
+ 'Option "Jacobian" will be ignored by this solver');
+ end
+ if (~isequal (vodeoptions.JPattern, vodetemp.JPattern))
+ warning ('OdePkg:InvalidOption', ...
+ 'Option "JPattern" will be ignored by this solver');
+ end
+ if (~isequal (vodeoptions.Vectorized, vodetemp.Vectorized))
+ warning ('OdePkg:InvalidOption', ...
+ 'Option "Vectorized" will be ignored by this solver');
+ end
+ if (~isequal (vodeoptions.NewtonTol, vodetemp.NewtonTol))
+ warning ('OdePkg:InvalidArgument', ...
+ 'Option "NewtonTol" will be ignored by this solver');
+ end
+ if (~isequal (vodeoptions.MaxNewtonIterations,...
+ vodetemp.MaxNewtonIterations))
+ warning ('OdePkg:InvalidArgument', ...
+ 'Option "MaxNewtonIterations" will be ignored by this solver');
+ end
+
+ %# Implementation of the option Mass has been finished. This option
+ %# can be set by the user to another value than default value.
+ if (~isempty (vodeoptions.Mass) && isnumeric (vodeoptions.Mass))
+ vhavemasshandle = false; vmass = vodeoptions.Mass; %# constant mass
+ elseif (isa (vodeoptions.Mass, 'function_handle'))
+ vhavemasshandle = true; %# mass defined by a function handle
+ else %# no mass matrix - creating a diag-matrix of ones for mass
+ vhavemasshandle = false; %# vmass = diag (ones (length (vinit), 1), 0);
+ end
+
+ %# Implementation of the option MStateDependence has been finished.
+ %# This option can be set by the user to another value than default
+ %# value.
+ if (strcmp (vodeoptions.MStateDependence, 'none'))
+ vmassdependence = false;
+ else vmassdependence = true;
+ end
+
+ %# Other options that are not used by this solver. Print a warning
+ %# message to tell the user that the option(s) is/are ignored.
+ if (~isequal (vodeoptions.MvPattern, vodetemp.MvPattern))
+ warning ('OdePkg:InvalidOption', ...
+ 'Option "MvPattern" will be ignored by this solver');
+ end
+ if (~isequal (vodeoptions.MassSingular, vodetemp.MassSingular))
+ warning ('OdePkg:InvalidOption', ...
+ 'Option "MassSingular" will be ignored by this solver');
+ end
+ if (~isequal (vodeoptions.InitialSlope, vodetemp.InitialSlope))
+ warning ('OdePkg:InvalidOption', ...
+ 'Option "InitialSlope" will be ignored by this solver');
+ end
+ if (~isequal (vodeoptions.MaxOrder, vodetemp.MaxOrder))
+ warning ('OdePkg:InvalidOption', ...
+ 'Option "MaxOrder" will be ignored by this solver');
+ end
+ if (~isequal (vodeoptions.BDF, vodetemp.BDF))
+ warning ('OdePkg:InvalidOption', ...
+ 'Option "BDF" will be ignored by this solver');
+ end
+
+ %# Starting the initialisation of the core solver ode78d
+ vtimestamp = vslot(1,1); %# timestamp = start time
+ vtimelength = length (vslot); %# length needed if fixed steps
+ vtimestop = vslot(1,vtimelength); %# stop time = last value
+
+ if (~vstepsizegiven)
+ vstepsize = vodeoptions.InitialStep;
+ vminstepsize = (vtimestop - vtimestamp) / (1/eps);
+ else %# If step size is given then use the fixed time steps
+ vstepsize = abs (vslot(1,1) - vslot(1,2));
+ vminstepsize = eps; %# vslot(1,2) - vslot(1,1) - eps;
+ end
+
+ vretvaltime = vtimestamp; %# first timestamp output
+ if (vhaveoutputselection) %# first solution output
+ vretvalresult = vinit(vodeoptions.OutputSel);
+ else vretvalresult = vinit;
+ end
+
+ %# Initialize the OutputFcn
+ if (vhaveoutputfunction)
+ feval (vodeoptions.OutputFcn, vslot', ...
+ vretvalresult', 'init', vfunarguments{:});
+ end
+
+ %# Initialize the History
+ if (isnumeric (vhist))
+ vhmat = vhist;
+ vhavehistnumeric = true;
+ else %# it must be a function handle
+ for vcnt = 1:length (vlags);
+ vhmat(:,vcnt) = feval (vhist, (vslot(1)-vlags(vcnt)), vfunarguments{:});
+ end
+ vhavehistnumeric = false;
+ end
+
+ %# Initialize DDE variables for history calculation
+ vsaveddetime = [vtimestamp - vlags, vtimestamp]';
+ vsaveddeinput = [vhmat, vinit']';
+ vsavedderesult = [vhmat, vinit']';
+
+ %# Initialize the EventFcn
+ if (vhaveeventfunction)
+ odepkg_event_handle (vodeoptions.Events, vtimestamp, ...
+ {vretvalresult', vhmat}, 'init', vfunarguments{:});
+ end
+
+ vpow = 1/8; %# MC2001: see p.91 in Ascher & Petzold
+ va = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0; %# The 7(8) coefficients
+ 1/18, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0; %# Coefficients proved, tt 20060827
+ 1/48, 1/16, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0;
+ 1/32, 0, 3/32, 0, 0, 0, 0, 0, 0, 0, 0, 0;
+ 5/16, 0, -75/64, 75/64, 0, 0, 0, 0, 0, 0, 0, 0;
+ 3/80, 0, 0, 3/16, 3/20, 0, 0, 0, 0, 0, 0, 0;
+ 29443841/614563906, 0, 0, 77736538/692538347, -28693883/1125000000, ...
+ 23124283/1800000000, 0, 0, 0, 0, 0, 0;
+ 16016141/946692911, 0, 0, 61564180/158732637, 22789713/633445777, ...
+ 545815736/2771057229, -180193667/1043307555, 0, 0, 0, 0, 0;
+ 39632708/573591083, 0, 0, -433636366/683701615, -421739975/2616292301, ...
+ 100302831/723423059, 790204164/839813087, 800635310/3783071287, 0, 0, 0, 0;
+ 246121993/1340847787, 0, 0, -37695042795/15268766246, -309121744/1061227803, ...
+ -12992083/490766935, 6005943493/2108947869, 393006217/1396673457, ...
+ 123872331/1001029789, 0, 0, 0;
+ -1028468189/846180014, 0, 0, 8478235783/508512852, 1311729495/1432422823, ...
+ -10304129995/1701304382, -48777925059/3047939560, 15336726248/1032824649, ...
+ -45442868181/3398467696, 3065993473/597172653, 0, 0;
+ 185892177/718116043, 0, 0, -3185094517/667107341, -477755414/1098053517, ...
+ -703635378/230739211, 5731566787/1027545527, 5232866602/850066563, ...
+ -4093664535/808688257, 3962137247/1805957418, 65686358/487910083, 0;
+ 403863854/491063109, 0, 0, -5068492393/434740067, -411421997/543043805, ...
+ 652783627/914296604, 11173962825/925320556, -13158990841/6184727034, ...
+ 3936647629/1978049680, -160528059/685178525, 248638103/1413531060, 0];
+ vb7 = [13451932/455176623; 0; 0; 0; 0; -808719846/976000145; ...
+ 1757004468/5645159321; 656045339/265891186; -3867574721/1518517206; ...
+ 465885868/322736535; 53011238/667516719; 2/45; 0];
+ vb8 = [14005451/335480064; 0; 0; 0; 0; -59238493/1068277825; 181606767/758867731; ...
+ 561292985/797845732; -1041891430/1371343529; 760417239/1151165299; ...
+ 118820643/751138087; -528747749/2220607170; 1/4];
+ vc = sum (va, 2);
+
+ %# The solver main loop - stop if the endpoint has been reached
+ vcntloop = 2; vcntcycles = 1; vu = vinit; vk = vu' * zeros(1,13);
+ vcntiter = 0; vunhandledtermination = true;
+ while ((vtimestamp < vtimestop && vstepsize >= vminstepsize))
+
+ %# Hit the endpoint of the time slot exactely
+ if ((vtimestamp + vstepsize) > vtimestop)
+ vstepsize = vtimestop - vtimestamp; end
+
+ %# Estimate the thirteen results when using this solver
+ for j = 1:13
+ vthetime = vtimestamp + vc(j,1) * vstepsize;
+ vtheinput = vu' + vstepsize * vk(:,1:j-1) * va(j,1:j-1)';
+ %# Claculate the history values (or get them from an external
+ %# function) that are needed for the next step of solving
+ if (vhavehistnumeric)
+ for vcnt = 1:length (vlags)
+ %# Direct implementation of a 'quadrature cubic Hermite interpolation'
+ %# found at the Faculty for Mathematics of the University of Stuttgart
+ %# http://mo.mathematik.uni-stuttgart.de/inhalt/aussage/aussage1269
+ vnumb = find (vthetime - vlags(vcnt) >= vsaveddetime);
+ velem = min (vnumb(end), length (vsaveddetime) - 1);
+ vstep = vsaveddetime(velem+1) - vsaveddetime(velem);
+ vdiff = (vthetime - vlags(vcnt) - vsaveddetime(velem)) / vstep;
+ vsubs = 1 - vdiff;
+ %# Calculation of the coefficients for the interpolation algorithm
+ vua = (1 + 2 * vdiff) * vsubs^2;
+ vub = (3 - 2 * vdiff) * vdiff^2;
+ vva = vstep * vdiff * vsubs^2;
+ vvb = -vstep * vsubs * vdiff^2;
+ vhmat(:,vcnt) = vua * vsaveddeinput(velem,:)' + ...
+ vub * vsaveddeinput(velem+1,:)' + ...
+ vva * vsavedderesult(velem,:)' + ...
+ vvb * vsavedderesult(velem+1,:)';
+ end
+ else %# the history must be a function handle
+ for vcnt = 1:length (vlags)
+ vhmat(:,vcnt) = feval ...
+ (vhist, vthetime - vlags(vcnt), vfunarguments{:});
+ end
+ end
+
+ if (vhavemasshandle) %# Handle only the dynamic mass matrix,
+ if (vmassdependence) %# constant mass matrices have already
+ vmass = feval ... %# been set before (if any)
+ (vodeoptions.Mass, vthetime, vtheinput, vfunarguments{:});
+ else %# if (vmassdependence == false)
+ vmass = feval ... %# then we only have the time argument
+ (vodeoptions.Mass, vthetime, vfunarguments{:});
+ end
+ vk(:,j) = vmass \ feval ...
+ (vfun, vthetime, vtheinput, vhmat, vfunarguments{:});
+ else
+ vk(:,j) = feval ...
+ (vfun, vthetime, vtheinput, vhmat, vfunarguments{:});
+ end
+ end
+
+ %# Compute the 7th and the 8th order estimation
+ y7 = vu' + vstepsize * (vk * vb7);
+ y8 = vu' + vstepsize * (vk * vb8);
+ if (vhavenonnegative)
+ vu(vodeoptions.NonNegative) = abs (vu(vodeoptions.NonNegative));
+ y7(vodeoptions.NonNegative) = abs (y7(vodeoptions.NonNegative));
+ y8(vodeoptions.NonNegative) = abs (y8(vodeoptions.NonNegative));
+ end
+ vSaveVUForRefine = vu;
+
+ %# Calculate the absolute local truncation error and the acceptable error
+ if (~vstepsizegiven)
+ if (~vnormcontrol)
+ vdelta = y8 - y7;
+ vtau = max (vodeoptions.RelTol * vu', vodeoptions.AbsTol);
+ else
+ vdelta = norm (y8 - y7, Inf);
+ vtau = max (vodeoptions.RelTol * max (norm (vu', Inf), 1.0), ...
+ vodeoptions.AbsTol);
+ end
+ else %# if (vstepsizegiven == true)
+ vdelta = 1; vtau = 2;
+ end
+
+ %# If the error is acceptable then update the vretval variables
+ if (all (vdelta <= vtau))
+ vtimestamp = vtimestamp + vstepsize;
+ vu = y8'; %# MC2001: the higher order estimation as "local extrapolation"
+ vretvaltime(vcntloop,:) = vtimestamp;
+ if (vhaveoutputselection)
+ vretvalresult(vcntloop,:) = vu(vodeoptions.OutputSel);
+ else
+ vretvalresult(vcntloop,:) = vu;
+ end
+ vcntloop = vcntloop + 1; vcntiter = 0;
+
+ %# Update DDE values for next history calculation
+ vsaveddetime(end+1) = vtimestamp;
+ vsaveddeinput(end+1,:) = vtheinput';
+ vsavedderesult(end+1,:) = vu;
+
+ %# Call plot only if a valid result has been found, therefore this
+ %# code fragment has moved here. Stop integration if plot function
+ %# returns false
+ if (vhaveoutputfunction)
+ if (vhaverefine) %# Do interpolation
+ for vcnt = 0:vodeoptions.Refine %# Approximation between told and t
+ vapproxtime = (vcnt + 1) * vstepsize / (vodeoptions.Refine + 2);
+ vapproxvals = vSaveVUForRefine' + vapproxtime * (vk * vb8);
+ if (vhaveoutputselection)
+ vapproxvals = vapproxvals(vodeoptions.OutputSel);
+ end
+ feval (vodeoptions.OutputFcn, (vtimestamp - vstepsize) + vapproxtime, ...
+ vapproxvals, [], vfunarguments{:});
+ end
+ end
+ vpltret = feval (vodeoptions.OutputFcn, vtimestamp, ...
+ vretvalresult(vcntloop-1,:)', [], vfunarguments{:});
+ if (vpltret), vunhandledtermination = false; break; end
+ end
+
+ %# Call event only if a valid result has been found, therefore this
+ %# code fragment has moved here. Stop integration if veventbreak is
+ %# true
+ if (vhaveeventfunction)
+ vevent = ...
+ odepkg_event_handle (vodeoptions.Events, vtimestamp, ...
+ {vu(:), vhmat}, [], vfunarguments{:});
+ if (~isempty (vevent{1}) && vevent{1} == 1)
+ vretvaltime(vcntloop-1,:) = vevent{3}(end,:);
+ vretvalresult(vcntloop-1,:) = vevent{4}(end,:);
+ vunhandledtermination = false; break;
+ end
+ end
+ end %# If the error is acceptable ...
+
+ %# Update the step size for the next integration step
+ if (~vstepsizegiven)
+ %# vdelta may be 0 or even negative - could be an iteration problem
+ vdelta = max (vdelta, eps);
+ vstepsize = min (vodeoptions.MaxStep, ...
+ min (0.8 * vstepsize * (vtau ./ vdelta) .^ vpow));
+ elseif (vstepsizegiven)
+ if (vcntloop < vtimelength)
+ vstepsize = vslot(1,vcntloop-1) - vslot(1,vcntloop-2);
+ end
+ end
+
+ %# Update counters that count the number of iteration cycles
+ vcntcycles = vcntcycles + 1; %# Needed for postprocessing
+ vcntiter = vcntiter + 1; %# Needed to find iteration problems
+
+ %# Stop solving because the last 1000 steps no successful valid
+ %# value has been found
+ if (vcntiter >= 5000)
+ error (['Solving has not been successful. The iterative', ...
+ ' integration loop exited at time t = %f before endpoint at', ...
+ ' tend = %f was reached. This happened because the iterative', ...
+ ' integration loop does not find a valid solution at this time', ...
+ ' stamp. Try to reduce the value of "InitialStep" and/or', ...
+ ' "MaxStep" with the command "odeset".\n'], vtimestamp, vtimestop);
+ end
+
+ end %# The main loop
+
+ %# Check if integration of the ode has been successful
+ if (vtimestamp < vtimestop)
+ if (vunhandledtermination == true)
+ error (['Solving has not been successful. The iterative', ...
+ ' integration loop exited at time t = %f', ...
+ ' before endpoint at tend = %f was reached. This may', ...
+ ' happen if the stepsize grows smaller than defined in', ...
+ ' vminstepsize. Try to reduce the value of "InitialStep" and/or', ...
+ ' "MaxStep" with the command "odeset".\n'], vtimestamp, vtimestop);
+ else
+ warning ('OdePkg:HideWarning', ...
+ ['Solver has been stopped by a call of "break" in', ...
+ ' the main iteration loop at time t = %f before endpoint at', ...
+ ' tend = %f was reached. This may happen because the @odeplot', ...
+ ' function returned "true" or the @event function returned "true".'], ...
+ vtimestamp, vtimestop);
+ end
+ end
+
+ %# Postprocessing, do whatever when terminating integration algorithm
+ if (vhaveoutputfunction) %# Cleanup plotter
+ feval (vodeoptions.OutputFcn, vtimestamp, ...
+ vretvalresult(vcntloop-1,:)', 'done', vfunarguments{:});
+ end
+ if (vhaveeventfunction) %# Cleanup event function handling
+ odepkg_event_handle (vodeoptions.Events, vtimestamp, ...
+ {vretvalresult(vcntloop-1,:), vhmat}, 'done', vfunarguments{:});
+ end
+
+ %# Print additional information if option Stats is set
+ if (strcmp (vodeoptions.Stats, 'on'))
+ vhavestats = true;
+ vnsteps = vcntloop-2; %# vcntloop from 2..end
+ vnfailed = (vcntcycles-1)-(vcntloop-2)+1; %# vcntcycl from 1..end
+ vnfevals = 13*(vcntcycles-1); %# number of ode evaluations
+ vndecomps = 0; %# number of LU decompositions
+ vnpds = 0; %# number of partial derivatives
+ vnlinsols = 0; %# no. of solutions of linear systems
+ %# Print cost statistics if no output argument is given
+ if (nargout == 0)
+ vmsg = fprintf (1, 'Number of successful steps: %d', vnsteps);
+ vmsg = fprintf (1, 'Number of failed attempts: %d', vnfailed);
+ vmsg = fprintf (1, 'Number of function calls: %d', vnfevals);
+ end
+ else vhavestats = false;
+ end
+
+ if (nargout == 1) %# Sort output variables, depends on nargout
+ varargout{1}.x = vretvaltime; %# Time stamps are saved in field x
+ varargout{1}.y = vretvalresult; %# Results are saved in field y
+ varargout{1}.solver = 'ode78d'; %# Solver name is saved in field solver
+ if (vhaveeventfunction)
+ varargout{1}.ie = vevent{2}; %# Index info which event occured
+ varargout{1}.xe = vevent{3}; %# Time info when an event occured
+ varargout{1}.ye = vevent{4}; %# Results when an event occured
+ end
+ if (vhavestats)
+ varargout{1}.stats = struct;
+ varargout{1}.stats.nsteps = vnsteps;
+ varargout{1}.stats.nfailed = vnfailed;
+ varargout{1}.stats.nfevals = vnfevals;
+ varargout{1}.stats.npds = vnpds;
+ varargout{1}.stats.ndecomps = vndecomps;
+ varargout{1}.stats.nlinsols = vnlinsols;
+ end
+ elseif (nargout == 2)
+ varargout{1} = vretvaltime; %# Time stamps are first output argument
+ varargout{2} = vretvalresult; %# Results are second output argument
+ elseif (nargout == 5)
+ varargout{1} = vretvaltime; %# Same as (nargout == 2)
+ varargout{2} = vretvalresult; %# Same as (nargout == 2)
+ varargout{3} = []; %# LabMat doesn't accept lines like
+ varargout{4} = []; %# varargout{3} = varargout{4} = [];
+ varargout{5} = [];
+ if (vhaveeventfunction)
+ varargout{3} = vevent{3}; %# Time info when an event occured
+ varargout{4} = vevent{4}; %# Results when an event occured
+ varargout{5} = vevent{2}; %# Index info which event occured
+ end
+ %# else nothing will be returned, varargout{1} undefined
+ end
+
+%! # We are using a "pseudo-DDE" implementation for all tests that
+%! # are done for this function. We also define an Events and a
+%! # pseudo-Mass implementation. For further tests we also define a
+%! # reference solution (computed at high accuracy) and an OutputFcn.
+%!function [vyd] = fexp (vt, vy, vz, varargin)
+%! vyd(1,1) = exp (- vt) - vz(1); %# The DDEs that are
+%! vyd(2,1) = vy(1) - vz(2); %# used for all examples
+%!function [vval, vtrm, vdir] = feve (vt, vy, vz, varargin)
+%! vval = fexp (vt, vy, vz); %# We use the derivatives
+%! vtrm = zeros (2,1); %# don't stop solving here
+%! vdir = ones (2,1); %# in positive direction
+%!function [vval, vtrm, vdir] = fevn (vt, vy, vz, varargin)
+%! vval = fexp (vt, vy, vz); %# We use the derivatives
+%! vtrm = ones (2,1); %# stop solving here
+%! vdir = ones (2,1); %# in positive direction
+%!function [vmas] = fmas (vt, vy, vz, varargin)
+%! vmas = [1, 0; 0, 1]; %# Dummy mass matrix for tests
+%!function [vmas] = fmsa (vt, vy, vz, varargin)
+%! vmas = sparse ([1, 0; 0, 1]); %# A dummy sparse matrix
+%!function [vref] = fref () %# The reference solution
+%! vref = [0.12194462133618, 0.01652432423938];
+%!function [vout] = fout (vt, vy, vflag, varargin)
+%! if (regexp (char (vflag), 'init') == 1)
+%! if (any (size (vt) ~= [2, 1])) error ('"fout" step "init"'); end
+%! elseif (isempty (vflag))
+%! if (any (size (vt) ~= [1, 1])) error ('"fout" step "calc"'); end
+%! vout = false;
+%! elseif (regexp (char (vflag), 'done') == 1)
+%! if (any (size (vt) ~= [1, 1])) error ('"fout" step "done"'); end
+%! else error ('"fout" invalid vflag');
+%! end
+%!
+%! %# Turn off output of warning messages for all tests, turn them on
+%! %# again if the last test is called
+%!error %# input argument number one
+%! warning ('off', 'OdePkg:InvalidOption');
+%! B = ode78d (1, [0 5], [1; 0], 1, [1; 0]);
+%!error %# input argument number two
+%! B = ode78d (@fexp, 1, [1; 0], 1, [1; 0]);
+%!error %# input argument number three
+%! B = ode78d (@fexp, [0 5], 1, 1, [1; 0]);
+%!error %# input argument number four
+%! B = ode78d (@fexp, [0 5], [1; 0], [1; 1], [1; 0]);
+%!error %# input argument number five
+%! B = ode78d (@fexp, [0 5], [1; 0], 1, 1);
+%!test %# one output argument
+%! vsol = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0]);
+%! assert ([vsol.x(end), vsol.y(end,:)], [5, fref], 0.2);
+%! assert (isfield (vsol, 'solver'));
+%! assert (vsol.solver, 'ode78d');
+%!test %# two output arguments
+%! [vt, vy] = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0]);
+%! assert ([vt(end), vy(end,:)], [5, fref], 0.2);
+%!test %# five output arguments and no Events
+%! [vt, vy, vxe, vye, vie] = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0]);
+%! assert ([vt(end), vy(end,:)], [5, fref], 0.2);
+%! assert ([vie, vxe, vye], []);
+%!test %# anonymous function instead of real function
+%! faym = @(vt, vy, vz) [exp(-vt) - vz(1); vy(1) - vz(2)];
+%! vsol = ode78d (faym, [0 5], [1; 0], 1, [1; 0]);
+%! assert ([vsol.x(end), vsol.y(end,:)], [5, fref], 0.2);
+%!test %# extra input arguments passed trhough
+%! vsol = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0], 'KL');
+%! assert ([vsol.x(end), vsol.y(end,:)], [5, fref], 0.2);
+%!test %# empty OdePkg structure *but* extra input arguments
+%! vopt = odeset;
+%! vsol = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0], vopt, 12, 13, 'KL');
+%! assert ([vsol.x(end), vsol.y(end,:)], [5, fref], 0.2);
+%!error %# strange OdePkg structure
+%! vopt = struct ('foo', 1);
+%! vsol = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0], vopt);
+%!test %# AbsTol option
+%! vopt = odeset ('AbsTol', 1e-5);
+%! vsol = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0], vopt);
+%! assert ([vsol.x(end), vsol.y(end,:)], [5, fref], 0.2);
+%!test %# AbsTol and RelTol option
+%! vopt = odeset ('AbsTol', 1e-7, 'RelTol', 1e-7);
+%! vsol = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0], vopt);
+%! assert ([vsol.x(end), vsol.y(end,:)], [5, fref], 0.2);
+%!test %# RelTol and NormControl option
+%! vopt = odeset ('AbsTol', 1e-7, 'NormControl', 'on');
+%! vsol = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0], vopt);
+%! assert ([vsol.x(end), vsol.y(end,:)], [5, fref], 0.2);
+%!test %# NonNegative for second component
+%! vopt = odeset ('NonNegative', 1);
+%! vsol = ode78d (@fexp, [0 2.5], [1; 0], 1, [1; 0], vopt);
+%! assert ([vsol.x(end), vsol.y(end,:)], [2.5, 0.001, 0.237], 0.2);
+%!test %# Details of OutputSel and Refine can't be tested
+%! vopt = odeset ('OutputFcn', @fout, 'OutputSel', 1, 'Refine', 5);
+%! vsol = ode78d (@fexp, [0 2.5], [1; 0], 1, [1; 0], vopt);
+%!test %# Stats must add further elements in vsol
+%! vopt = odeset ('Stats', 'on');
+%! vsol = ode78d (@fexp, [0 2.5], [1; 0], 1, [1; 0], vopt);
+%! assert (isfield (vsol, 'stats'));
+%! assert (isfield (vsol.stats, 'nsteps'));
+%!test %# InitialStep option
+%! vopt = odeset ('InitialStep', 1e-8);
+%! vsol = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0], vopt);
+%! assert ([vsol.x(end), vsol.y(end,:)], [5, fref], 0.2);
+%!test %# MaxStep option
+%! vopt = odeset ('MaxStep', 1e-2);
+%! vsol = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0], vopt);
+%! assert ([vsol.x(end), vsol.y(end,:)], [5, fref], 0.2);
+%!test %# Events option add further elements in vsol
+%! vopt = odeset ('Events', @feve);
+%! vsol = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0], vopt);
+%! assert (isfield (vsol, 'ie'));
+%! assert (vsol.ie, [1; 1]);
+%! assert (isfield (vsol, 'xe'));
+%! assert (isfield (vsol, 'ye'));
+%!test %# Events option, now stop integration
+%! warning ('off', 'OdePkg:HideWarning');
+%! vopt = odeset ('Events', @fevn, 'NormControl', 'on');
+%! vsol = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0], vopt);
+%! assert ([vsol.ie, vsol.xe, vsol.ye], ...
+%! [1.0000, 2.9219, -0.2127, -0.2671], 0.2);
+%!test %# Events option, five output arguments
+%! vopt = odeset ('Events', @fevn, 'NormControl', 'on');
+%! [vt, vy, vxe, vye, vie] = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0], vopt);
+%! assert ([vie, vxe, vye], ...
+%! [1.0000, 2.9219, -0.2127, -0.2671], 0.2);
+%!
+%! %# test for Jacobian option is missing
+%! %# test for Jacobian (being a sparse matrix) is missing
+%! %# test for JPattern option is missing
+%! %# test for Vectorized option is missing
+%! %# test for NewtonTol option is missing
+%! %# test for MaxNewtonIterations option is missing
+%!
+%!test %# Mass option as function
+%! vopt = odeset ('Mass', eye (2,2));
+%! vsol = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0], vopt);
+%! assert ([vsol.x(end), vsol.y(end,:)], [5, fref], 0.2);
+%!test %# Mass option as matrix
+%! vopt = odeset ('Mass', eye (2,2));
+%! vsol = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0], vopt);
+%! assert ([vsol.x(end), vsol.y(end,:)], [5, fref], 0.2);
+%!test %# Mass option as sparse matrix
+%! vopt = odeset ('Mass', sparse (eye (2,2)));
+%! vsol = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0], vopt);
+%! assert ([vsol.x(end), vsol.y(end,:)], [5, fref], 0.2);
+%!test %# Mass option as function and sparse matrix
+%! vopt = odeset ('Mass', @fmsa);
+%! vsol = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0], vopt);
+%! assert ([vsol.x(end), vsol.y(end,:)], [5, fref], 0.2);
+%!test %# Mass option as function and MStateDependence
+%! vopt = odeset ('Mass', @fmas, 'MStateDependence', 'strong');
+%! vsol = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0], vopt);
+%! assert ([vsol.x(end), vsol.y(end,:)], [5, fref], 0.2);
+%!test %# Set BDF option to something else than default
+%! vopt = odeset ('BDF', 'on');
+%! [vt, vy] = ode78d (@fexp, [0 5], [1; 0], 1, [1; 0], vopt);
+%! assert ([vt(end), vy(end,:)], [5, fref], 0.5);
+%!
+%! %# test for MvPattern option is missing
+%! %# test for InitialSlope option is missing
+%! %# test for MaxOrder option is missing
+%!
+%! warning ('on', 'OdePkg:InvalidOption');
+
+%# Local Variables: ***
+%# mode: octave ***
+%# End: ***