cocontraction_line

 varargout = MUSCLE_COCONTRACTION(muscle1,muscle2) computes co-contraction indices for
      muscle pairs (muscle 1 and muscle2)

 ARGUMENTS
  muscle1      ...   n x 1 or 1 x n  vector of processed EMG data
  muscle2      ...   n x 1 or 1 x n  vector of processed EMG data
  method       ...   Choice of algorithm to use. Choices: 'Rudolph',
                     'Falconer', 'Lo2017'. See notes for more details.
  plotGraph    ...   Choice to plot graph (boolean). Default false

 RETURNS
  cc (co-contraction indices)          ...   n x 1  vector of co-contraction indices 
                                             in case of Rudolph and Falconer
 (or)
  cc (common area curve) and cc_value  ...   (1) n x 1  vector of minima form two curves 
                                             used to estimate co-contraction incase
                                             of Lo2017 (2)  co-contraction value

 NOTES
 - Algorithm choices:
   (a) Rudolph et al. 2000. Dynamic stability after ACL injury: who can hop?
       Knee Surg Sports Traumatol Arthrosc 8, 262-269 (commented)
   (b) Falconer, K., Winter, D., 1985. Quantitative assessment of co-contraction at the
       ankle joint in walking. Electromyogr. Clin. Neurophysiol. 25, 135–149.
       (This option is commented out in the code below)
    (c) Justine Lo, On-Yee Lo, Erin A. Olson, Daniel Habtemariam, Ikechukwu Iloputaife, Margaret M. Gagnon, Brad Manor, Lewis A. Lipsitz,
       Functional implications of muscle co-contraction during gait in advanced age. Gait & Posture,Volume 53,2017,Pages 110-114,
       ISSN 0966-6362,
       https://doi.org/10.1016/j.gaitpost.2017.01.010.

 Created by Philippe C. Dixon Nov 21 2017

 See also knee_OA_cocontraction