def read(filename):
"""This will read any VTK file! It will figure out what reader to use
then wrap the VTK object for use in ``vtki``
"""
def legacy(filename):
reader = vtk.vtkDataSetReader()
reader.SetFileName(filename)
reader.Update()
return reader.GetOutputDataObject(0)
ext = os.path.splitext(filename)[1]
if ext.lower() in '.vtk':
# Use a legacy reader and wrap the result
return wrap(legacy(filename))
else:
# From the extension, decide which reader to use
if ext.lower() in '.vti': # ImageData
return vtki.UniformGrid(filename)
elif ext.lower() in '.vtr': # RectilinearGrid
return vtki.RectilinearGrid(filename)
elif ext.lower() in '.vtu': # UnstructuredGrid
return vtki.UnstructuredGrid(filename)
elif ext.lower() in '.ply': # PolyData
return vtki.PolyData(filename)
elif ext.lower() in '.vts': # UnstructuredGrid
return vtki.StructuredGrid(filename)
else:
# Attempt to use the legacy reader...
try:
return wrap(legacy(filename))
except:
pass
raise IOError("This file was not able to be automatically read by vtki.")
def test_uniform_setters():
grid = vtki.UniformGrid()
grid.dimensions = (10, 10, 10)
assert grid.GetDimensions() == (10, 10, 10)
grid.spacing = (5, 2, 1)
assert grid.GetSpacing() == (5, 2, 1)
grid.origin = (6, 27.7, 19.8)
assert grid.GetOrigin() == (6, 27.7, 19.8)
def test_create_uniform_grid_from_specs():
# create UniformGrid
dims = [10, 10, 10]
grid = vtki.UniformGrid(dims) # Using default spacing and origin
assert grid.dimensions == [10, 10, 10]
assert grid.origin == [0.0, 0.0, 0.0]
assert grid.spacing == [1.0, 1.0, 1.0]
spacing = [2, 1, 5]
grid = vtki.UniformGrid(dims, spacing) # Usign default origin
assert grid.dimensions == [10, 10, 10]
assert grid.origin == [0.0, 0.0, 0.0]
assert grid.spacing == [2.0, 1.0, 5.0]
origin = [10, 35, 50]
grid = vtki.UniformGrid(dims, spacing, origin) # Everything is specified
assert grid.dimensions == [10, 10, 10]
assert grid.origin == [10.0, 35.0, 50.0]
assert grid.spacing == [2.0, 1.0, 5.0]
assert grid.dimensions == [10, 10, 10]
def test_create_uniform_grid_from_specs():
# create UniformGrid
dims = (10, 10, 10)
grid = vtki.UniformGrid(dims) # Using default spacing and origin
assert grid.dimensions == (10, 10, 10)
assert grid.origin == (0.0, 0.0, 0.0)
assert grid.spacing == (1.0, 1.0, 1.0)
spacing = (2, 1, 5)
grid = vtki.UniformGrid(dims, spacing) # Usign default origin
assert grid.dimensions == (10, 10, 10)
assert grid.origin == (0.0, 0.0, 0.0)
assert grid.spacing == (2.0, 1.0, 5.0)
origin = (10, 35, 50)
grid = vtki.UniformGrid(dims, spacing, origin) # Everything is specified
assert grid.dimensions == (10, 10, 10)
assert grid.origin == (10.0, 35.0, 50.0)
assert grid.spacing == (2.0, 1.0, 5.0)
assert grid.dimensions == (10, 10, 10)
def test_save_uniform(extension, binary, tmpdir):
filename = str(tmpdir.mkdir("tmpdir").join('tmp.%s' % extension))
ogrid = examples.load_uniform()
ogrid.save(filename, binary)
grid = vtki.UniformGrid(filename)
assert grid.n_cells == ogrid.n_cells
assert grid.origin == ogrid.origin
assert grid.spacing == ogrid.spacing
assert grid.dimensions == ogrid.dimensions
def numpy_to_texture(image):
"""Convert a NumPy image array to a vtk.vtkTexture"""
if not isinstance(image, np.ndarray):
raise TypeError('Unknown input type ({})'.format(type(image)))
if image.ndim != 3 or image.shape[2] != 3:
raise AssertionError('Input image must be nn by nm by RGB')
grid = vtki.UniformGrid((image.shape[1], image.shape[0], 1))
grid.point_arrays['Image'] = np.flip(image.swapaxes(0, 1), axis=1).reshape(
(-1, 3), order='F')
grid.set_active_scalar('Image')
return image_to_texture(grid)
def test_compute_cell_sizes():
for i, dataset in enumerate(datasets):
result = dataset.compute_cell_sizes()
assert result is not None
assert isinstance(result, type(dataset))
assert 'Area' in result.scalar_names
assert 'Volume' in result.scalar_names
# Test the volume property
grid = vtki.UniformGrid((10, 10, 10))
volume = float(np.prod(np.array(grid.dimensions) - 1))
assert np.allclose(grid.volume, volume)
def read(filename, attrs=None):
"""This will read any VTK file! It will figure out what reader to use
then wrap the VTK object for use in ``vtki``.
Parameters
----------
attrs : dict, optional
A dictionary of attributes to call on the reader. Keys of dictionary are
the attribute/method names and values are the arguments passed to those
calls. If you do not have any attributes to call, pass ``None`` as the
value.
"""
filename = os.path.abspath(os.path.expanduser(filename))
ext = get_ext(filename)
# From the extension, decide which reader to use
if attrs is not None:
reader = get_reader(filename)
return standard_reader_routine(reader, filename, attrs=attrs)
elif ext in '.vti': # ImageData
return vtki.UniformGrid(filename)
elif ext in '.vtr': # RectilinearGrid
return vtki.RectilinearGrid(filename)
elif ext in '.vtu': # UnstructuredGrid
return vtki.UnstructuredGrid(filename)
elif ext in ['.ply', '.obj', '.stl']: # PolyData
return vtki.PolyData(filename)
elif ext in '.vts': # StructuredGrid
return vtki.StructuredGrid(filename)
elif ext in ['.vtm', '.vtmb']:
return vtki.MultiBlock(filename)
elif ext in ['.e', '.exo']:
return read_exodus(filename)
elif ext in ['.vtk']:
# Attempt to use the legacy reader...
return read_legacy(filename)
else:
# Attempt find a reader in the readers mapping
try:
reader = get_reader(filename)
return standard_reader_routine(reader, filename)
except KeyError:
pass
raise IOError("This file was not able to be automatically read by vtki.")
def test_grid_points():
"""Test the points mehtods on UniformGrid and inearGrid"""
points = np.array([[0, 0, 0], [1, 0, 0], [1, 1, 0], [0, 1, 0], [0, 0, 1],
[1, 0, 1], [1, 1, 1], [0, 1, 1]])
grid = vtki.UniformGrid()
grid.points = points
assert grid.dimensions == [2, 2, 2]
assert grid.spacing == [1, 1, 1]
assert grid.origin == [0., 0., 0.]
assert np.allclose(np.unique(grid.points, axis=0), np.unique(points,
axis=0))
opts = np.c_[grid.x, grid.y, grid.z]
assert np.allclose(np.unique(opts, axis=0), np.unique(points, axis=0))
# Now test rectilinear grid
del grid
grid = vtki.RectilinearGrid()
grid.points = points
assert grid.dimensions == [2, 2, 2]
assert np.allclose(np.unique(grid.points, axis=0), np.unique(points,
axis=0))
# Take a 3D NumPy array of data values that holds some spatial data where each # axis corresponds to the XYZ cartesian axes. This example will create a # :class:`vtki.UniformGrid` object that will hold the spatial reference for a # 3D grid which a 3D NumPy array of values can be plotted against. import vtki import numpy as np ################################################################################ # Create the 3D NumPy array of spatially referenced data # This is spatially referenced such that the grid is 20 by 5 by 10 (nx by ny by nz) values = np.linspace(0, 10, 1000).reshape((20, 5, 10)) values.shape # Create the spatial reference grid = vtki.UniformGrid() # Set the grid dimensions: shape + 1 because we want to inject our values on the CELL data grid.dimensions = np.array(values.shape) + 1 # Edit the spatial reference grid.origin = (100, 33, 55.6) # The bottom left corner of the data set grid.spacing = (1, 5, 2) # These are the cell sizes along each axis # Add the data values to the cell data grid.cell_arrays['values'] = values.flatten(order='F') # Flatten the array! # Now plot the grid! grid.plot(show_edges=True) ################################################################################
def load_uniform():
""" Loads a sample uniform grid """
return vtki.UniformGrid(uniformfile)
