title: How to solve an ill-conditioned system of linear equations in python?
body: <p>I am solving a linear system of few equations (6 equations that has complex coefficients) with <code>numpy.linalg.solve(A, b)</code>, where the arrays have <code>type="complex128"</code>. The system is solved for a big range of frequencies and from a certain frequency on, the system becomes very much ill-conditioned. When the condition number is in my case over <code>1E+19</code> the system becomes unstable so I do not get right solutions. I have tried to use <code>"clongdouble"</code> type but it is not supported in <code>numpy.linalg</code>.</p>
  
  <p>Are there ideas which is the best workaround to increase the precision or to get the system stable in numpy?</p>