ph-math/src/main/java/com/helger/numbercruncher/mathutils/Complex.java
public Complex subtract (final Complex z)
  {
    return new Complex (m_fReal - z.real (), m_fImaginary - z.imaginary ());
  }
public Complex subtract (final Complex z)
  {
    return new Complex (m_fReal - z.real (), m_fImaginary - z.imaginary ());
  }
Subtract another complex number from this one.

@param z
the other complex number
@return a new complex number that is the difference