a[n - 1] = deltaX[n - 2] / 3.0;
c[n - 2] = deltaX[n - 2] / 6.0;
}
final TridiagonalMatrix tridiagonal = new TridiagonalMatrix(a, b, c);
return invertor.evaluate(tridiagonal);
}
@Override
public void setYValueAtIndex(final int index, final double y) {
ArgumentChecker.notNegative(index, "index");