Section: Visualization Toolkit Common Classes
To get and set array values, the vtkTypedArray template class derives from vtkArray and provides type-specific methods for retrieval and update.
Two concrete derivatives of vtkTypedArray are provided at the moment: vtkDenseArray and vtkSparseArray, which provide dense and sparse storage for arbitrary-dimension data, respectively. Toolkit users can create their own concrete derivatives that implement alternative storage strategies, such as compressed-sparse-row, etc. You could also create an array that provided read-only access to 'virtual' data, such as an array that returned a Fibonacci sequence, etc.
To create an instance of class vtkArray, simply invoke its constructor as follows
obj = vtkArray
obj
is an instance of the vtkArray class.
string = obj.GetClassName ()
int = obj.IsA (string name)
vtkArray = obj.NewInstance ()
vtkArray = obj.SafeDownCast (vtkObject o)
bool = obj.IsDense ()
- Returns true iff the underlying array storage is "dense", i.e. that GetSize() and
GetNonNullSize() will always return the same value. If not, the array is "sparse".
obj.Resize (vtkIdType i)
- Resizes the array to the given extents (number of dimensions and size of each dimension).
Note that concrete implementations of vtkArray may place constraints on the the extents
that they will store, so you cannot assume that GetExtents() will always return the same
value passed to Resize().
The contents of the array are undefined after calling Resize() - you should
initialize its contents accordingly. In particular, dimension-labels will be
undefined, dense array values will be undefined, and sparse arrays will be
empty.
obj.Resize (vtkIdType i, vtkIdType j)
- Resizes the array to the given extents (number of dimensions and size of each dimension).
Note that concrete implementations of vtkArray may place constraints on the the extents
that they will store, so you cannot assume that GetExtents() will always return the same
value passed to Resize().
The contents of the array are undefined after calling Resize() - you should
initialize its contents accordingly. In particular, dimension-labels will be
undefined, dense array values will be undefined, and sparse arrays will be
empty.
obj.Resize (vtkIdType i, vtkIdType j, vtkIdType k)
- Resizes the array to the given extents (number of dimensions and size of each dimension).
Note that concrete implementations of vtkArray may place constraints on the the extents
that they will store, so you cannot assume that GetExtents() will always return the same
value passed to Resize().
The contents of the array are undefined after calling Resize() - you should
initialize its contents accordingly. In particular, dimension-labels will be
undefined, dense array values will be undefined, and sparse arrays will be
empty.
vtkIdType = obj.GetDimensions ()
- Returns the number of dimensions stored in the array. Note that this is the same as
calling GetExtents().GetDimensions().
vtkIdType = obj.GetSize ()
- Returns the number of values stored in the array. Note that this is the same as calling
GetExtents().GetSize(), and represents the maximum number of values that could ever
be stored using the current extents. This is equal to the number of values stored in a
dense array, but may be larger than the number of values stored in a sparse array.
vtkIdType = obj.GetNonNullSize ()
- Returns the number of non-null values stored in the array. Note that this
value will equal GetSize() for dense arrays, and will be less-than-or-equal
to GetSize() for sparse arrays.
obj.SetName (vtkStdString &name)
- Sets the array name.
vtkStdString = obj.GetName ()
- Returns the array name.
obj.SetDimensionLabel (vtkIdType i, vtkStdString &label)
- Sets the label for the i-th array dimension.
vtkStdString = obj.GetDimensionLabel (vtkIdType i)
- Returns the label for the i-th array dimension.
vtkArray = obj.DeepCopy ()
- Returns a new array that is a deep copy of this array.