extractIR

 Extract impulse response from swept-sine response.
   [irLin, irNonLin] = extractIR(sweep_response, invsweepfft) 
   Extracts the impulse response from the swept-sine response.  Use
   synthSweep.m first to create the stimulus; then pass it through the
   device under test; finally, take the response and process it with the
   inverse swept-sine to produce the linear impulse response and
   non-linear simplified Volterra diagonals.  The location of each
   non-linear order can be calculated with the sweepRate - this will be
   implemented as a future revision.
   
   Developed at Oygo Sound LLC

   Equations from Muller and Massarani, "Transfer Function Measurement
   with Sweeps."

   Modified by Jacob Donley (jrd089@uowmail.edu.au) (January 2017)