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/*
ARPACK++ v1.0 8/1/1997
c++ interface to ARPACK code.
MODULE LNMatrxF.h
Funtion template that generates a tridiagonal nonsymmetric matrix.
ARPACK Authors
Richard Lehoucq
Danny Sorensen
Chao Yang
Dept. of Computational & Applied Mathematics
Rice University
Houston, Texas
*/
#ifndef LNMATRXF_H
#define LNMATRXF_H
template<class FLOAT, class INT>
void NonSymMatrixF(INT n, INT& nnz, FLOAT* &A, INT* &irow, INT* &pcol)
{
INT i,j;
FLOAT diag, sub;
// Defining constants.
sub = 1.0;
diag = 4.0;
// Defining the number of nonzero matrix elements.
nnz = 3*n-2;
// Creating output vectors.
A = new FLOAT[nnz];
irow = new INT[nnz];
pcol = new INT[n+1];
// Filling A, irow and pcol.
pcol[0] = 0;
j = 0;
for (i=0; i!=n; i++) {
if (i != 0) {
irow[j] = i-1;
A[j++] = sub;
}
irow[j] = i;
A[j++] = diag;
if (i != (n-1)) {
irow[j] = i+1;
A[j++] = sub;
}
pcol[i+1] = j;
}
} // NonSymMatrixF.
#endif // LNMATRXF_H
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