class_docstr: Interface for executable reg_transform from NiftyReg platform.
  
  Tools to convert transformation parametrisation from one type to another
  as well as to compose, inverse or half transformations.
  
  `Source code <https://cmiclab.cs.ucl.ac.uk/mmodat/niftyreg>`_
  
  Examples
  --------
  >>> from nipype.interfaces import niftyreg
  >>> node = niftyreg.RegTransform()
  >>> node.inputs.def_input = 'warpfield.nii'
  >>> node.inputs.omp_core_val = 4
  >>> node.cmdline  # doctest: +ELLIPSIS
  'reg_transform -omp 4 -def warpfield.nii .../warpfield_trans.nii.gz'
class_docstr_tok: ["Interface","for","executable","reg_transform","from","NiftyReg","platform",".","Tools","to","convert","transformation","parametrisation","from","one","type","to","another","as","well","as","to","compose",",","inverse","or","half","transformations",".","`","Source","code","<","https",":","\/\/cmiclab.cs.ucl.ac.uk\/mmodat\/niftyreg",">","`","_","Examples","--","--","--","--",">",">",">","from","nipype.interfaces","import","niftyreg",">",">",">","node","=","niftyreg.RegTransform","(",")",">",">",">","node.inputs.def_input","=","'warpfield.nii'",">",">",">","node.inputs.omp_core_val","=","4",">",">",">","node.cmdline","#","doctest",":","+ELLIPSIS","'reg_transform","-omp","4","-def","warpfield.nii","...","\/warpfield_trans.nii.gz","'"]
code: def _list_outputs(self):
      outputs = self.output_spec().get()
  
      if isdefined(self.inputs.out_file):
          outputs["out_file"] = self.inputs.out_file
      else:
          outputs["out_file"] = self._gen_filename("out_file")
  
      return outputs
  
imports: import os
  from ..base import TraitedSpec, File, traits, isdefined
  from .base import get_custom_path, NiftyRegCommand, NiftyRegCommandInputSpec
  from ...utils.filemanip import split_filename
label_desc: Use image node_id 3 for calling the RegTransform obj's underlying member method code with example usage: obj._list_outputs() and returns: outputs