def _cell_scalar(self, name=None):
"""
Returns the cell scalars of a vtk object
Parameters
----------
name : str
Name of cell scalars to retrive.
Returns
-------
scalars : np.ndarray
Numpy array of scalars
"""
if name is None:
# use active scalar array
field, name = self.active_scalar_info
if field != CELL_DATA_FIELD:
raise RuntimeError('Must specify an array to fetch.')
vtkarr = self.GetCellData().GetAbstractArray(name)
if vtkarr is None:
raise AssertionError('({}) is not a cell scalar'.format(name))
# numpy does not support bit array data types
if isinstance(vtkarr, vtk.vtkBitArray):
vtkarr = vtk_bit_array_to_char(vtkarr)
if name not in self._cell_bool_array_names:
self._cell_bool_array_names.append(name)
array = convert_array(vtkarr)
if array.dtype == np.uint8 and name in self._cell_bool_array_names:
array = array.view(np.bool)
return array
def _field_scalar(self, name=None):
"""
Returns field scalars of a vtk object
Parameters
----------
name : str
Name of field scalars to retrive.
Returns
-------
scalars : np.ndarray
Numpy array of scalars
"""
if name is None:
raise RuntimeError('Must specify an array to fetch.')
vtkarr = self.GetFieldData().GetAbstractArray(name)
if vtkarr is None:
raise AssertionError(
'({}) is not a valid field scalar array'.format(name))
# numpy does not support bit array data types
if isinstance(vtkarr, vtk.vtkBitArray):
vtkarr = vtk_bit_array_to_char(vtkarr)
if name not in self._point_bool_array_names:
self._field_bool_array_names.append(name)
array = convert_array(vtkarr)
if array.dtype == np.uint8 and name in self._field_bool_array_names:
array = array.view(np.bool)
return array
def _row_array(self, name=None):
"""Return row scalars of a vtk object.
Parameters
----------
name : str
Name of row scalars to retrieve.
Return
------
scalars : np.ndarray
Numpy array of scalars
"""
if name is None:
# use first array
name = self.GetRowData().GetArrayName(0)
if name is None:
raise RuntimeError('No arrays present to fetch.')
vtkarr = self.GetRowData().GetAbstractArray(name)
if vtkarr is None:
raise AssertionError('({}) is not a row scalar'.format(name))
# numpy does not support bit array data types
if isinstance(vtkarr, vtk.vtkBitArray):
vtkarr = vtk_bit_array_to_char(vtkarr)
if name not in self._row_bool_array_names:
self._row_bool_array_names.append(name)
array = convert_array(vtkarr)
if array.dtype == np.uint8 and name in self._row_bool_array_names:
array = array.view(np.bool)
return array
def _add_point_scalar(self, scalars, name, set_active=False, deep=True):
"""
Adds point scalars to the mesh
Parameters
----------
scalars : numpy.ndarray
Numpy array of scalars. Must match number of points.
name : str
Name of point scalars to add.
set_active : bool, optional
Sets the scalars to the active plotting scalars. Default False.
deep : bool, optional
Does not copy scalars when False. A reference to the scalars
must be kept to avoid a segfault.
"""
if scalars is None:
raise TypeError('Empty array unable to be added')
if not isinstance(scalars, np.ndarray):
scalars = np.array(scalars)
if scalars.shape[0] != self.n_points:
raise Exception('Number of scalars must match the number of ' +
'points')
# need to track which arrays are boolean as all boolean arrays
# must be stored as uint8
if scalars.dtype == np.bool:
scalars = scalars.view(np.uint8)
if name not in self._point_bool_array_names:
self._point_bool_array_names.append(name)
if not scalars.flags.c_contiguous:
scalars = np.ascontiguousarray(scalars)
vtkarr = convert_array(scalars, deep=deep)
vtkarr.SetName(name)
self.GetPointData().AddArray(vtkarr)
if set_active or self.active_scalar_info[1] is None:
self.GetPointData().SetActiveScalars(name)
self._active_scalar_info = [POINT_DATA_FIELD, name]
def _add_cell_scalar(self, scalars, name, set_active=False, deep=True):
"""
Adds cell scalars to the vtk object.
Parameters
----------
scalars : numpy.ndarray
Numpy array of scalars. Must match number of points.
name : str
Name of point scalars to add.
set_active : bool, optional
Sets the scalars to the active plotting scalars. Default False.
deep : bool, optional
Does not copy scalars when False. A reference to the scalars
must be kept to avoid a segfault.
"""
if scalars is None:
raise TypeError('Empty array unable to be added')
if not isinstance(scalars, np.ndarray):
scalars = np.array(scalars)
if scalars.shape[0] != self.n_cells:
raise Exception(
'Number of scalars must match the number of cells (%d)' %
self.n_cells)
if not scalars.flags.c_contiguous:
raise AssertionError('Array must be contigious')
if scalars.dtype == np.bool:
scalars = scalars.view(np.uint8)
self._cell_bool_array_names.append(name)
vtkarr = convert_array(scalars, deep=deep)
vtkarr.SetName(name)
self.GetCellData().AddArray(vtkarr)
if set_active or self.active_scalar_info[1] is None:
self.GetCellData().SetActiveScalars(name)
self._active_scalar_info = [CELL_DATA_FIELD, name]
def _add_row_array(self, scalars, name, deep=True):
"""
Adds scalars to the vtk object.
Parameters
----------
scalars : numpy.ndarray
Numpy array of scalars. Must match number of points.
name : str
Name of point scalars to add.
deep : bool, optional
Does not copy scalars when False. A reference to the scalars
must be kept to avoid a segfault.
"""
if scalars is None:
raise TypeError('Empty array unable to be added')
if not isinstance(scalars, np.ndarray):
scalars = np.array(scalars)
if self.n_rows == 0 or self.n_columns == 0:
self.n_rows = scalars.shape[0]
elif scalars.shape[0] != self.n_rows:
raise Exception(
'Number of scalars must match the number of rows (%d)' %
self.n_rows)
if not scalars.flags.c_contiguous:
scalars = np.ascontiguousarray(scalars)
if scalars.dtype == np.bool:
scalars = scalars.view(np.uint8)
self._row_bool_array_names.append(name)
vtkarr = convert_array(scalars, deep=deep)
vtkarr.SetName(name)
self.AddColumn(vtkarr)
def _add_field_scalar(self, scalars, name, deep=True):
"""
Adds field scalars to the mesh
Parameters
----------
scalars : numpy.ndarray
Numpy array of scalars. Does not have to match number of points or
numbers of cells.
name : str
Name of field scalars to add.
deep : bool, optional
Does not copy scalars when False. A reference to the scalars
must be kept to avoid a segfault.
"""
if scalars is None:
raise TypeError('Empty array unable to be added')
if not isinstance(scalars, np.ndarray):
scalars = np.array(scalars)
# need to track which arrays are boolean as all boolean arrays
# must be stored as uint8
if scalars.dtype == np.bool:
scalars = scalars.view(np.uint8)
if name not in self._field_bool_array_names:
self._field_bool_array_names.append(name)
if not scalars.flags.c_contiguous:
scalars = np.ascontiguousarray(scalars)
vtkarr = convert_array(scalars, deep=deep)
vtkarr.SetName(name)
self.GetFieldData().AddArray(vtkarr)