old_contents: import numpy as np
  import os
  import matplotlib.pyplot as plt
  import math
  import AnalysisTools as at
  
  ## Reading probes into the file
  folder = "output"
  os.chdir(folder)
  probes = 'record_rectangle1.csv'        
          
  datalist = at.readProbeFile(probes)
  probeType = datalist[0]
  time = datalist[1]
  data = datalist[2]
  rotq_e3 = data[:,7]
  
  alpha = []
  for i in range(0,len(rotq_e3)):
      alpha.append(2*math.asin(rotq_e3[i]))
      alpha[i] *= 360/(2*math.pi)
  alpha = np.array(alpha)
  
  it = np.where(time>2.5)[0][0]
  period = at.zeroCrossing(time[:it],alpha[:it])[0]
  
  period_ref = 0.93
  err = abs(period_ref-period)/abs(period_ref)
  val = open('validation_FCC.txt', 'w')
  val.write('Period for the rotation angle'+'\n')
  val.write('Theory'+'\t'+'Simulation'+'\t'+'Error (%)'+'\n')
  val.write(str(period_ref)+'\t'+str(period)+'\t'+str(err))
  val.close()
  
  plt.plot(time,alpha)
  plt.xlabel('time [sec]')
  plt.ylabel('rotation angle [deg]')
  plt.suptitle('Rotation angle for the floating caisson 2D')
  plt.xlim((0.,4.5))
  plt.grid(True)
  plt.savefig('rotation_angle.png')
  plt.show()
  
new_contents: import numpy as np
  import os
  import matplotlib.pyplot as plt
  import math
  import AnalysisTools as at
  
  ## Reading probes into the file
  folder = "output"
  os.chdir(folder)
  probes = 'record_rectangle1.csv'        
          
  datalist = at.readProbeFile(probes)
  probeType = datalist[0]
  time = datalist[1]
  data = datalist[2]
  rotq_e3 = data[:,7]
  
  alpha = []
  for i in range(0,len(rotq_e3)):
      alpha.append(2*math.asin(rotq_e3[i]))
      alpha[i] *= 360/(2*math.pi)
  alpha = np.array(alpha)
  
  it = np.where(time>2.5)[0][0]
  period = at.zeroCrossing(time[:it],alpha[:it],up=False)[0]
  
  period_ref = 0.93
  err = abs(period_ref-period)/abs(period_ref)
  val = open('validation_FCC.txt', 'w')
  val.write('Period for the rotation angle'+'\n')
  val.write('Theory'+'\t'+'Simulation'+'\t'+'Error (%)'+'\n')
  val.write(str(period_ref)+'\t'+str(period)+'\t'+str(err))
  val.close()
  
  plt.plot(time,alpha)
  plt.xlabel('time [sec]')
  plt.ylabel('rotation angle [deg]')
  plt.suptitle('Rotation angle for the floating caisson 2D')
  plt.xlim((0.,4.5))
  plt.grid(True)
  plt.savefig('rotation_angle.png')
  plt.show()
  
subject: Update postprocess_FCC.py