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// Copyright (C) 2003-2005 Johan Jansson and Anders Logg.
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// Copyright (C) 2003-2006 Johan Jansson and Anders Logg.
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// Licensed under the GNU GPL Version 2.
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// Last changed: 2005-11-10
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// First added: 2003-10-21
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// Last changed: 2006-08-21
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#include <dolfin/constants.h>
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#include <dolfin/Event.h>
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#include <dolfin/uBlasVector.h>
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#include <dolfin/uBlasSparseMatrix.h>
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#include <dolfin/Dependencies.h>
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#include <dolfin/Sample.h>
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/// A ODE represents an initial value problem of the form
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/// u'(t) = f(u(t),t) on (0,T],
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/// where u(t) is a vector of length N.
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/// To define an ODE, a user must create a subclass of ODE and
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/// create the function u0() defining the initial condition, as well
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/// the function f() defining the right-hand side.
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/// DOLFIN provides two types of ODE solvers: a set of standard
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/// mono-adaptive solvers with equal adaptive time steps for all
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/// components as well as a set of multi-adaptive solvers with
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/// individual and adaptive time steps for the different
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/// components. The right-hand side f() is defined differently for
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/// the two sets of methods, with the multi-adaptive solvers
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/// requiring a component-wise evaluation of the right-hand
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/// side. Only one right-hand side function f() needs to be defined
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/// for use of any particular solver.
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/// It is also possible to solve implicit systems of the form
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/// M(u(t), t) u'(t) = f(u(t),t) on (0,T],
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/// by setting the option "implicit" to true and defining the
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/// Create an ODE of size N with final time T
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ODE(uint N, real T);
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/// Return initial value for given component
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virtual real u0(uint i) = 0;
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/// Evaluate right-hand side (multi-adaptive version)
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// FIXME:: make this abstract?
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virtual real f(const real u[], real t, uint i);
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/// Evaluate right-hand side (mono-adaptive version)
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virtual void f(const real u[], real t, real y[]);
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/// Compute product y = Mx for implicit system
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virtual void M(const real x[], real y[], const real u[], real t);
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/// Compute product y = Jx for Jacobian J
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virtual void J(const real x[], real y[], const real u[], real t);
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/// Jacobian (optional)
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virtual real dfdu(const real u[], real t, uint i, uint j);
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/// Time step to use for whole system (optional)
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/// Set initial values
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virtual void u0(uBlasVector& u) = 0;
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/// Evaluate right-hand side y = f(u, t), mono-adaptive version (default, optional)
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virtual void f(const uBlasVector& u, real t, uBlasVector& y);
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/// Evaluate right-hand side f_i(u, t), multi-adaptive version (optional)
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virtual real f(const uBlasVector& u, real t, uint i);
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/// Compute product y = Mx for implicit system (optional)
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virtual void M(const uBlasVector& x, uBlasVector& y, const uBlasVector& u, real t);
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/// Compute product y = Jx for Jacobian J (optional)
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virtual void J(const uBlasVector& x, uBlasVector& y, const uBlasVector& u, real t);
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/// Compute entry of Jacobian (optional)
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virtual real dfdu(const uBlasVector& u, real t, uint i, uint j);
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/// Time step to use for the whole system at a given time t (optional)
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virtual real timestep(real t, real k0) const;
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/// Time step to use for given component (optional)
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/// Time step to use for a given component at a given time t (optional)
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virtual real timestep(real t, uint i, real k0) const;
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/// Update ODE, return false to stop (optional)
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virtual bool update(const real u[], real t, bool end);
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virtual bool update(const uBlasVector& u, real t, bool end);
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/// Save sample (optional)
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virtual void save(Sample& sample);
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/// Number of components N
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/// Automatically detect sparsity (optional)
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/// Compute sparsity from given matrix (optional)
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void sparse(const uBlasSparseMatrix& A);
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/// Return number of components N
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/// End time (final time)
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/// Return end time (final time T)
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real endtime() const;
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/// Automatically detect sparsity
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/// Compute sparsity from given matrix
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void sparse(const Matrix& A);
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friend class Dual;
added
removed
src/kernel/ode/dolfin/ODE.h
