/usr/share/octave/site/m/sundialsTB/idas/function_types/IDAPrecSolveFn.m is in octave-sundials 2.5.0-3+b1.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 | %IDAPrecSolveFn - type for preconditioner solve function.
%
% The user-supplied preconditioner solve function PSOLFUN
% is to solve a linear system P z = r, where P is the
% preconditioner matrix.
%
% The function PSOLFUN must be defined as
% FUNCTION [Z, FLAG] = PSOLFUN(T,YY,YP,RR,R)
% and must return a vector Z containing the solution of Pz=r.
% If PSOLFUN was successful, it must return FLAG=0. For a recoverable
% error (in which case the step will be retried) it must set FLAG to a
% positive value. If an unrecoverable error occurs, it must set FLAG
% to a negative value, in which case the integration will be halted.
% The input argument RR contains the current value of f(t,yy,yp).
%
% If a user data structure DATA was specified in IDAInit, then
% PSOLFUN must be defined as
% FUNCTION [Z, FLAG, NEW_DATA] = PSOLFUN(T,YY,YP,RR,R,DATA)
% If the local modifications to the user data structure are needed in
% other user-provided functions then, besides setting the vector Z and
% the flag FLAG, the PSOLFUN function must also set NEW_DATA. Otherwise,
% it should set NEW_DATA=[] (do not set NEW_DATA = DATA as it would
% lead to unnecessary copying).
%
% See also IDAPrecSetupFn, IDASetOptions
%
% NOTE: PSOLFUN and PSOLFUNB are specified through the property
% PrecSolveFn to IDASetOptions and are used only if the property
% LinearSolver was set to 'GMRES', 'BiCGStab', or 'TFQMR'.
% Radu Serban <radu@llnl.gov>
% Copyright (c) 2007, The Regents of the University of California.
% $Revision: 1.3 $Date: 2011/05/26 00:01:23 $
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