// OPPOSITE
// Opposite of a Phasor matrix
public PhasorMatrix opposite() {
PhasorMatrix opp = PhasorMatrix.copy(this);
for (int i = 0; i < this.nrow; i++) {
for (int j = 0; j < this.ncol; j++) {
opp.matrix[i][j] = this.matrix[i][j].times(Phasor.minusOne());
}
}
return opp;
}
// COMPLEX CONJUGATE
// Complex Conjugate of a Phasor matrix
public PhasorMatrix conjugate() {
PhasorMatrix conj = PhasorMatrix.copy(this);
for (int i = 0; i < this.nrow; i++) {
for (int j = 0; j < this.ncol; j++) {
conj.matrix[i][j] = this.matrix[i][j].conjugate();
}
}
return conj;
}
// LU DECOMPOSITION OF COMPLEX MATRIX A
// For details of LU decomposition
// See Numerical Recipes, The Art of Scientific Computing
// by W H Press, S A Teukolsky, W T Vetterling & B P Flannery
// Cambridge University Press, http://www.nr.com/
// PhasorMatrix ludmat is the returned LU decompostion
// int[] index is the vector of row permutations
// dswap returns +1.0 for even number of row interchanges
// returns -1.0 for odd number of row interchanges
public PhasorMatrix luDecomp() {
if (this.nrow != this.ncol) throw new IllegalArgumentException("A matrix is not square");
int n = this.nrow;
int imax = 0;
double dum = 0.0D, temp = 0.0D, big = 0.0D;
double[] vv = new double[n];
Phasor sum = new Phasor();
Phasor dumm = new Phasor();
PhasorMatrix ludmat = PhasorMatrix.copy(this);
Phasor[][] ludarray = ludmat.getArrayReference();
ludmat.dswap = 1.0;
for (int i = 0; i < n; i++) {
big = 0.0;
for (int j = 0; j < n; j++) {
if ((temp = ludarray[i][j].abs()) > big) big = temp;
}
if (big == 0.0) throw new ArithmeticException("Singular matrix");
vv[i] = 1.0 / big;
}
for (int j = 0; j < n; j++) {
for (int i = 0; i < j; i++) {
sum = Phasor.copy(ludarray[i][j]);
for (int k = 0; k < i; k++) sum.minusEquals(ludarray[i][k].times(ludarray[k][j]));
ludarray[i][j] = Phasor.copy(sum);
}
big = 0.0;
for (int i = j; i < n; i++) {
sum = Phasor.copy(ludarray[i][j]);
for (int k = 0; k < j; k++) {
sum.minusEquals(ludarray[i][k].times(ludarray[k][j]));
}
ludarray[i][j] = Phasor.copy(sum);
if ((dum = vv[i] * sum.abs()) >= big) {
big = dum;
imax = i;
}
}
if (j != imax) {
for (int k = 0; k < n; k++) {
dumm = Phasor.copy(ludarray[imax][k]);
ludarray[imax][k] = Phasor.copy(ludarray[j][k]);
ludarray[j][k] = Phasor.copy(dumm);
}
ludmat.dswap = -ludmat.dswap;
vv[imax] = vv[j];
}
ludmat.index[j] = imax;
if (ludarray[j][j].isZero()) {
ludarray[j][j].reset(TINY, 0.0D);
}
if (j != n - 1) {
dumm = ludarray[j][j].inverse();
for (int i = j + 1; i < n; i++) {
ludarray[i][j].timesEquals(dumm);
}
}
}
return ludmat;
}
// ADJOIN
// Adjoin of a Phasor matrix
public PhasorMatrix adjoin() {
PhasorMatrix adj = PhasorMatrix.copy(this);
adj = adj.transpose();
adj = adj.conjugate();
return adj;
}