New question #112556 on DOLFIN:
https://answers.launchpad.net/dolfin/+question/112556
I am attempting to use LinearSolver in C++ to do some simple matrix and vector
solution, as in 3x3 or 5x5. I get this error.
[0]PETSC ERROR: --------------------- Error Message
------------------------------------
[0]PETSC ERROR: Object is in wrong state!
[0]PETSC ERROR: Not for unassembled matrix!
[0]PETSC ERROR:
------------------------------------------------------------------------
[0]PETSC ERROR: Petsc Release Version 3.0.0, Patch 8, Fri Aug 21 14:02:12 CDT
2009
This seems to suggest that I cannot use LinearSolver in the code directly, that
instead I have to make a form file. Is this in fact the case? and if so how
would I make that form file?
This is my code in case it is relevant. I am doing some simple interpolation to
calculate a step size for an iterative non-linear problem. This is the test
program I wrote.
int main()
{
//declare and initialise
int degree = 4;
double *x = new double[degree + 1];
double *y = new double[degree + 1];
std::vector<dolfin::uint> columns;
std::vector<double> values;
dolfin::LinearSolver linSolver;
dolfin::Matrix X(degree + 1, degree + 1);
dolfin::Vector Y(degree + 1);
dolfin::Vector A(degree + 1);
//generate test points
x[0] = 0;
y[0] = 0;
x[1] = 1;
y[1] = -2;
x[2] = 2;
y[2] = -1;
x[3] = 3;
y[3] = -2;
x[4] = 4;
y[4] = 0;
//set vector
Y.set_local(y);
//set matrix
for (int j = 0; j <= degree; j ++)
columns.push_back(dolfin::uint(j));
for (dolfin::uint row = 0; row < dolfin::uint(degree); row++){
for (int j = 0; j <= degree; j++)
values.push_back( power(x[row], (degree - j) ) );
X.setrow(row, columns, values);
values.clear();
}
//solve [X]{A} = {Y} where A is the coefficients of the polynomial
linSolver.solve(X, A, Y);
//output
for (int j = 0; j <= degree; j++)
std::cout << A[j] << std::endl;
//clean up
delete [] x;
delete [] y;
}
Any help is appreciated. Thank you.
You received this question notification because you are a member of
DOLFIN Team, which is an answer contact for DOLFIN.
_______________________________________________
Mailing list: https://launchpad.net/~dolfin
Post to : [email protected]
Unsubscribe : https://launchpad.net/~dolfin
More help : https://help.launchpad.net/ListHelp
