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comparison scripts/sparse/bicgstab.m @ 10793:be55736a0783

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Grammarcheck the documentation from m-files.
author Rik <octave@nomad.inbox5.com>
date Sun, 18 Jul 2010 20:35:16 -0700
parents 1673a0dc019f
children 1740012184f9
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10792:91342260063e 10793:be55736a0783
15 ## You should have received a copy of the GNU General Public License 15 ## You should have received a copy of the GNU General Public License
16 ## along with Octave; see the file COPYING. If not, see 16 ## along with Octave; see the file COPYING. If not, see
17 ## <http://www.gnu.org/licenses/>. 17 ## <http://www.gnu.org/licenses/>.
18 18
19 ## -*- texinfo -*- 19 ## -*- texinfo -*-
20 ## @deftypefn {Function File} {} bicgstab (@var{A}, @var{b}) 20 ## @deftypefn {Function File} {} bicgstab (@var{A}, @var{b})
21 ## @deftypefnx {Function File} {} bicgstab (@var{A}, @var{b}, @var{tol}, @var{maxit}, @var{M1}, @var{M2}, @var{x0}) 21 ## @deftypefnx {Function File} {} bicgstab (@var{A}, @var{b}, @var{tol}, @var{maxit}, @var{M1}, @var{M2}, @var{x0})
22 ## This procedure attempts to solve a system of linear equations A*x = b for x. 22 ## This procedure attempts to solve a system of linear equations A*x = b for x.
23 ## The @var{A} must be square, symmetric and positive definite real matrix N*N. 23 ## The @var{A} must be square, symmetric and positive definite real matrix N*N.
24 ## The @var{b} must be a one column vector with a length of N. 24 ## The @var{b} must be a one column vector with a length of N.
25 ## The @var{tol} specifies the tolerance of the method, the default value is 1e-6. 25 ## The @var{tol} specifies the tolerance of the method, the default value is
26 ## The @var{maxit} specifies the maximum number of iterations, the default value is min(20,N). 26 ## 1e-6.
27 ## The @var{M1} specifies a preconditioner, can also be a function handler which returns M\X. 27 ## The @var{maxit} specifies the maximum number of iterations, the default value
28 ## The @var{M2} combined with @var{M1} defines preconditioner as preconditioner=M1*M2. 28 ## is min(20,N).
29 ## The @var{M1} specifies a preconditioner, can also be a function handler which
30 ## returns M\X.
31 ## The @var{M2} combined with @var{M1} defines preconditioner as
32 ## preconditioner=M1*M2.
29 ## The @var{x0} is the initial guess, the default value is zeros(N,1). 33 ## The @var{x0} is the initial guess, the default value is zeros(N,1).
30 ## 34 ##
31 ## The value @var{x} is a computed result of this procedure. 35 ## The value @var{x} is a computed result of this procedure.
32 ## The value @var{flag} can be 0 when we reach tolerance in @var{maxit} iterations, 1 when 36 ## The value @var{flag} can be 0 when we reach tolerance in @var{maxit}
33 ## we don't reach tolerance in @var{maxit} iterations and 3 when the procedure stagnates. 37 ## iterations, 1 when
38 ## we don't reach tolerance in @var{maxit} iterations and 3 when the procedure
39 ## stagnates.
34 ## The value @var{relres} is a relative residual - norm(b-A*x)/norm(b). 40 ## The value @var{relres} is a relative residual - norm(b-A*x)/norm(b).
35 ## The value @var{iter} is an iteration number in which x was computed. 41 ## The value @var{iter} is an iteration number in which x was computed.
36 ## The value @var{resvec} is a vector of @var{relres} for each iteration. 42 ## The value @var{resvec} is a vector of @var{relres} for each iteration.
37 ## 43 ##
38 ## @end deftypefn 44 ## @end deftypefn