ENH: added argparse support for neuroimaging files

fsl/utils/parse_data.py

+#!/usr/bin/env python
+#
+# Support for neuroimage data in argparse
+#
+# Author: Michiel Cottaar <michiel.cottaar@ndcn.ox.ac.uk
+#
+"""This module contains support for neuroimaging data in argparse
+
+Argparse is the built-in python library for resolving command line arguments.
+
+The functions in this module can be passed on to the ``type`` argument in the ``ArgumentParser.add_command`` method
+to interpret command line arguments as neuroimageing objects (.e.g, NIFTI image files)
+
+
+.. autosummary::
+   :nosignatures:
+
+    Image
+    Mesh
+    Atlas
+"""
+
+
+from fsl.data import image, gifti, vtk, atlases
+from fsl.utils import path
+import argparse
+
+
+def Image(filename):
+    """
+    Reads in an image from a NIFTI or Analyze file.
+
+    :arg filename: filename provided by the user
+    :return: fsl.data.image.Image object
+    """
+    try:
+        full_filename = image.addExt(filename)
+    except path.PathError as e:
+        raise argparse.ArgumentTypeError(*e.args)
+    return image.Image(full_filename)
+
+
+def Mesh(filename):
+    """
+    Reads in a mesh from either a GIFTI (.surf.gii) or a VTK (.vtk) file
+
+    :param filename: filename provided by the user
+    :return: GIFTI or VTK sub-class of fsl.data.mesh.Mesh
+    """
+    try:
+        full_filename = path.addExt(filename, ['.surf.gii', '.vtk'])
+    except path.PathError as e:
+        raise argparse.ArgumentTypeError(*e.args)
+    if path.hasExt(full_filename, '.surf.gii'):
+        return gifti.GiftiMesh(full_filename)
+    else:
+        return vtk.VTKMesh(full_filename)
+
+
+def Atlas(name):
+    """
+    Reads in the atlas from the FSL standard atlases
+
+    :param name: name of the atlas
+    :return: fsl.data.atlases.Atlas representation of an FSL atlas
+    """
+    atlases.rescanAtlases()
+    if not atlases.hasAtlas(name):
+        atlas_names = tuple(desc.atlasID for desc in atlases.listAtlases())
+        raise argparse.ArgumentTypeError('Requested atlas %r not one of: %r' % (name, atlas_names))
+    return atlases.loadAtlas(name)
+
+
+

fsl/wrappers/wrapperutils.py

@@ -305,7 +305,7 @@ def applyArgStyle(style, valsep=None, argmap=None, valmap=None, **kwargs):
 
 def namedPositionals(func, args):
     """Given a function, and a sequence of positional arguments destined
-    for that function, identiifes the name for each positional argument.
+    for that function, identifies the name for each positional argument.
     Variable positional arguments are given an automatic name.
 
     :arg func: Function which will accept ``args`` as positionals.

tests/test_parse_data.py

+#!/usr/bin/env python
+#
+# test_parse_data.py -
+#
+# Author: Michiel Cottaar <Michiel.Cottaar@ndcn.ox.ac.uk>
+#
+
+import argparse
+from fsl.utils import parse_data, tempdir
+import os.path as op
+from fsl.data.vtk import VTKMesh
+from fsl.data.gifti import GiftiMesh
+from fsl.data.image import Image
+from fsl.data.atlases import Atlas
+from pytest import raises
+from .test_image import make_image
+
+
+datadir = op.join(op.dirname(__file__), 'testdata')
+
+
+def test_mesh():
+    mesh_parser = argparse.ArgumentParser("Reads a VTK file")
+    mesh_parser.add_argument("mesh", type=parse_data.Mesh)
+
+    real_filename = op.join(datadir, 'test_mesh.vtk')
+    args = mesh_parser.parse_args([real_filename])
+    assert isinstance(args.mesh, VTKMesh)
+
+    real_filename = op.join(datadir, 'test_mesh')
+    args = mesh_parser.parse_args([real_filename])
+    assert isinstance(args.mesh, VTKMesh)
+
+    real_filename = op.join(datadir, 'example.surf.gii')
+    args = mesh_parser.parse_args([real_filename])
+    assert isinstance(args.mesh, GiftiMesh)
+
+    real_filename = op.join(datadir, 'example')
+    args = mesh_parser.parse_args([real_filename])
+    assert isinstance(args.mesh, GiftiMesh)
+
+    fake_filename = op.join(datadir, 'test_mesh_fake.vtk')
+    with raises(SystemExit):
+        mesh_parser.parse_args([fake_filename])
+
+    fake_filename = op.join(datadir, 'example.shape.gii')
+    with raises(SystemExit):
+        mesh_parser.parse_args([fake_filename])
+
+
+def test_image():
+    with tempdir.tempdir() as testdir:
+        image_parser = argparse.ArgumentParser("Reads an image")
+        image_parser.add_argument("image", type=parse_data.Image)
+
+        for filetype in range(3):
+            filename = op.join(testdir, 'image%r' % filetype)
+            make_image(filename, filetype)
+            args = image_parser.parse_args([filename])
+            assert isinstance(args.image, Image)
+            if filetype == 0:
+                args = image_parser.parse_args([filename + '.hdr'])
+                assert isinstance(args.image, Image)
+                args = image_parser.parse_args([filename + '.img'])
+                assert isinstance(args.image, Image)
+                with raises(SystemExit):
+                    image_parser.parse_args([filename + '.nii'])
+                with raises(SystemExit):
+                    image_parser.parse_args([filename + '.nii.gz'])
+            else:
+                args = image_parser.parse_args([filename + '.nii'])
+                assert isinstance(args.image, Image)
+
+                with raises(SystemExit):
+                    image_parser.parse_args([filename + '.img'])
+                with raises(SystemExit):
+                    image_parser.parse_args([filename + '.hdr'])
+                with raises(SystemExit):
+                    image_parser.parse_args([filename + '.nii.gz'])
+
+        double_filename = op.join(testdir, 'image1')
+        make_image(double_filename, 0)
+        with raises(SystemExit):
+            image_parser.parse_args([double_filename])
+
+
+def test_atlas():
+    atlas_parser = argparse.ArgumentParser('reads an atlas')
+    atlas_parser.add_argument('atlas', type=parse_data.Atlas)
+
+    args = atlas_parser.parse_args(['cerebellum_mniflirt'])
+    assert isinstance(args.atlas, Atlas)
+
+    with raises(SystemExit):
+        atlas_parser.parse_args(['fake'])
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