code: def plot_d_delta_m(fignum, Bdm, DdeltaM, s):
      
      plt.figure(num=fignum)
      plt.clf()
      if not isServer:
          plt.figtext(.02, .01, version_num)
      start = len(Bdm) - len(DdeltaM)
      plt.plot(Bdm[start:], DdeltaM, 'b')
      plt.xlabel('B (T)')
      plt.ylabel('d (Delta M)/dB')
      plt.title(s)
docs: function to plot d (Delta M)/dB  curves
  
      Parameters
      __________
      fignum : matplotlib figure number
      Bdm : change in field
      Ddelta M : change in delta M
      s : specimen name