class_docstr: Calculates a tensor metric volume from a tensor volume.
  
  Example
  -------
  >>> from nipype.interfaces import dtitk
  >>> node = dtitk.TVtool()
  >>> node.inputs.in_file = 'im1.nii'
  >>> node.inputs.in_flag = 'fa'
  >>> node.cmdline
  'TVtool -in im1.nii -fa -out im1_fa.nii'
  >>> node.run() # doctest: +SKIP
class_docstr_tok: ["Calculates","a","tensor","metric","volume","from","a","tensor","volume",".","Example","--","--","--","-",">",">",">","from","nipype.interfaces","import","dtitk",">",">",">","node","=","dtitk.TVtool","(",")",">",">",">","node.inputs.in_file","=","'im1.nii'",">",">",">","node.inputs.in_flag","=","'fa'",">",">",">","node.cmdline","'TVtool","-in","im1.nii","-fa","-out","im1_fa.nii'",">",">",">","node.run","(",")","#","doctest",":","+SKIP"]
code: def _list_outputs(self):
      outputs = self._outputs().get()
      out_file = self.inputs.out_file
      if not isdefined(out_file):
          out_file = self._gen_filename("out_file")
      outputs["out_file"] = os.path.abspath(out_file)
      return outputs
  
imports: from ..base import TraitedSpec, CommandLineInputSpec, File, traits, isdefined
  from ...utils.filemanip import fname_presuffix
  from .base import CommandLineDtitk, DTITKRenameMixin
  import os
label_desc: Use image node_id 1 for calling the TVtool obj's underlying member method code with example usage: obj._list_outputs() and returns: outputs