docstr: This function calculates the volume of detection error as defined in
  Wack et al.
  
  :return: DE: Total volume of detection error, DEFP: Detection error
      false positives, DEFN: Detection error false negatives
docstr_tok: ["This","function","calculates","the","volume","of","detection","error","as","defined","in","Wack","et","al",".",":","return",":","DE",":","Total","volume","of","detection","error",",","DEFP",":","Detection","error","false","positives",",","DEFN",":","Detection","error","false","negatives"]
code: def detection_error(self):
      """
      This function calculates the volume of detection error as defined in
      Wack et al.
  
      :return: DE: Total volume of detection error, DEFP: Detection error
          false positives, DEFN: Detection error false negatives
      """
      TPcMap, FNcMap, FPcMap = self.connected_errormaps()
      DEFN = np.sum(FNcMap)
      DEFP = np.sum(FPcMap)
      return DEFN + DEFP, DEFP, DEFN
  
imports: from __future__ import absolute_import, print_function
  import numpy
  from scipy import ndimage
  from niftynet.utilities.util_common import MorphologyOps, CacheFunctionOutput
label_desc: Use image node_id 43 for calling the PairwiseMeasures obj's underlying member method code with example usage: obj.detection_error() and returns: unknown,  DEFP,  DEFN