code: def matthews_correl_coeff(ntp, ntn, nfp, nfn):
      '''
      This calculates the Matthews correlation coefficent.
  
      https://en.wikipedia.org/wiki/Matthews_correlation_coefficient
  
      Parameters
      ----------
  
      ntp : int
          The number of true positives.
  
      ntn : int
          The number of true negatives
  
      nfp : int
          The number of false positives.
  
      nfn : int
          The number of false negatives.
  
      Returns
      -------
  
      float
          The Matthews correlation coefficient.
  
      '''
  
      mcc_top = (ntp*ntn - nfp*nfn)
      mcc_bot = msqrt((ntp + nfp)*(ntp + nfn)*(ntn + nfp)*(ntn + nfn))
  
      if mcc_bot > 0:
          return mcc_top/mcc_bot
      else:
          return np.naf matthews_correl_coeff(ntp, ntn, nfp, nfn):
      '''
      This calculates the Matthews correlation coefficent.
  
      https://en.wikipedia.org/wiki/Matthews_correlation_coefficient
  
      Parameters
      ----------
  
      ntp : int
          The number of true positives.
  
      ntn : int
          The number of true negatives
  
      nfp : int
          The number of false positives.
  
      nfn : int
          The number of false negatives.
  
      Returns
      -------
  
      float
          The Matthews correlation coefficient.
  
      '''
  
      mcc_top = (ntp*ntn - nfp*nfn)
      mcc_bot = msqrt((ntp + nfp)*(ntp + nfn)*(ntn + nfp)*(ntn + nfn))
  
      if mcc_bot > 0:
          return mcc_top/mcc_bot
      else:
          return np.nan
docs: This calculates the Matthews correlation coefficent.
  
      https://en.wikipedia.org/wiki/Matthews_correlation_coefficient
  
      Parameters
      ----------
  
      ntp : int
          The number of true positives.
  
      ntn : int
          The number of true negatives
  
      nfp : int
          The number of false positives.
  
      nfn : int
          The number of false negatives.
  
      Returns
      -------
  
      float
          The Matthews correlation coefficient.