# xarray.DataTree ### *class* xarray.DataTree(dataset=None, children=None, name=None)[[source]](https://github.com/pydata/xarray/blob/main/xarray/core/datatree.py#L478-L2736) A tree-like hierarchical collection of xarray objects. Attempts to present an API like that of xarray.Dataset, but methods are wrapped to also update all the tree’s child nodes. #### \_\_init_\_(dataset=None, children=None, name=None)[[source]](https://github.com/pydata/xarray/blob/main/xarray/core/datatree.py#L533-L566) Create a single node of a DataTree. The node may optionally contain data in the form of data and coordinate variables, stored in the same way as data is stored in an xarray.Dataset. * **Parameters:** * **dataset** ([`Dataset`](xarray.Dataset.html.md#xarray.Dataset), *optional*) – Data to store directly at this node. * **children** (`Mapping[str`, `DataTree]`, *optional*) – Any child nodes of this node. * **name** ([`str`](https://docs.python.org/3/builtins/stdtypes.html#str), *optional*) – Name for this node of the tree. * **Returns:** [`DataTree`](#xarray.DataTree) #### SEE ALSO [`DataTree.from_dict`](xarray.DataTree.from_dict.html.md#xarray.DataTree.from_dict) ### Methods | [`__init__`](#xarray.DataTree.__init__)([dataset, children, name]) | Create a single node of a DataTree. | |------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | [`all`](xarray.DataTree.all.html.md#xarray.DataTree.all)([dim, keep_attrs]) | Reduce this DataTree's data by applying `all` along some dimension(s). | | [`any`](xarray.DataTree.any.html.md#xarray.DataTree.any)([dim, keep_attrs]) | Reduce this DataTree's data by applying `any` along some dimension(s). | | [`argsort`](xarray.DataTree.argsort.html.md#xarray.DataTree.argsort)([axis, kind, order, stable, descending]) | Returns the indices that would sort this array. | | [`assign`](xarray.DataTree.assign.html.md#xarray.DataTree.assign)([items]) | Assign new data variables or child nodes to a DataTree, returning a new object with all the original items in addition to the new ones. | | [`chunk`](xarray.DataTree.chunk.html.md#xarray.DataTree.chunk)([chunks, name_prefix, token, lock, ...]) | Coerce all arrays in all groups in this tree into dask arrays with the given chunks. | | `close`() | Close any files associated with this tree. | | [`compute`](xarray.DataTree.compute.html.md#xarray.DataTree.compute)(\*\*kwargs) | Manually trigger loading and/or computation of this datatree's data from disk or a remote source into memory and return a new datatree. | | [`conj`](xarray.DataTree.conj.html.md#xarray.DataTree.conj)() | Complex-conjugate all elements. | | [`conjugate`](xarray.DataTree.conjugate.html.md#xarray.DataTree.conjugate)(\*args, \*\*kwargs) | a.conj() | | [`copy`](xarray.DataTree.copy.html.md#xarray.DataTree.copy)(\*[, inherit, deep]) | Returns a copy of this subtree. | | `count`([dim, keep_attrs]) | Reduce this DataTree's data by applying `count` along some dimension(s). | | [`cumprod`](xarray.DataTree.cumprod.html.md#xarray.DataTree.cumprod)([dim, skipna, keep_attrs]) | Reduce this DataTree's data by applying `cumprod` (i.e., cumulative product) along some dimension(s). | | [`cumsum`](xarray.DataTree.cumsum.html.md#xarray.DataTree.cumsum)([dim, skipna, keep_attrs]) | Reduce this DataTree's data by applying `cumsum` (i.e., cumulative sum) along some dimension(s). | | [`drop_nodes`](xarray.DataTree.drop_nodes.html.md#xarray.DataTree.drop_nodes)(names, \*[, errors]) | Drop child nodes from this node. | | [`equals`](xarray.DataTree.equals.html.md#xarray.DataTree.equals)(other) | Two DataTrees are equal if they have isomorphic node structures, with matching node names, and if they have matching variables and coordinates, all of which are equal. | | [`filter`](xarray.DataTree.filter.html.md#xarray.DataTree.filter)(filterfunc) | Filter nodes according to a specified condition. | | [`filter_like`](xarray.DataTree.filter_like.html.md#xarray.DataTree.filter_like)(other) | Filter a datatree like another datatree. | | [`find_common_ancestor`](xarray.DataTree.find_common_ancestor.html.md#xarray.DataTree.find_common_ancestor)(other) | Find the first common ancestor of two nodes in the same tree. | | [`from_dict`](xarray.DataTree.from_dict.html.md#xarray.DataTree.from_dict)([data, coords, name, nested]) | Create a datatree from a dictionary of data objects, organised by paths into the tree. | | [`get`](xarray.DataTree.get.html.md#xarray.DataTree.get)(key[, default]) | Access child nodes, variables, or coordinates stored in this node. | | [`identical`](xarray.DataTree.identical.html.md#xarray.DataTree.identical)(other) | Like equals, but also checks attributes on all datasets, variables and coordinates, and requires that any inherited coordinates at the tree root are also inherited on the other tree. | | [`isel`](xarray.DataTree.isel.html.md#xarray.DataTree.isel)([indexers, drop, missing_dims]) | Returns a new data tree with each array indexed along the specified dimension(s). | | [`isomorphic`](xarray.DataTree.isomorphic.html.md#xarray.DataTree.isomorphic)(other) | Two DataTrees are considered isomorphic if the set of paths to their descendent nodes are the same. | | [`items`](xarray.DataTree.items.html.md#xarray.DataTree.items)() | | | [`iter_lineage`](xarray.DataTree.iter_lineage.html.md#xarray.DataTree.iter_lineage)() | Iterate up the tree, starting from the current node. | | [`keys`](xarray.DataTree.keys.html.md#xarray.DataTree.keys)() | | | [`load`](xarray.DataTree.load.html.md#xarray.DataTree.load)(\*\*kwargs) | Manually trigger loading and/or computation of this datatree's data from disk or a remote source into memory and return this datatree. | | [`map_over_datasets`](xarray.DataTree.map_over_datasets.html.md#xarray.DataTree.map_over_datasets)(func, \*args[, kwargs]) | Apply a function to every dataset in this subtree, returning a new tree which stores the results. | | [`match`](xarray.DataTree.match.html.md#xarray.DataTree.match)(pattern) | Return nodes with paths matching pattern. | | [`max`](xarray.DataTree.max.html.md#xarray.DataTree.max)([dim, skipna, keep_attrs]) | Reduce this DataTree's data by applying `max` (i.e., maximum) along some dimension(s). | | [`mean`](xarray.DataTree.mean.html.md#xarray.DataTree.mean)([dim, skipna, keep_attrs]) | Reduce this DataTree's data by applying `mean` along some dimension(s). | | [`median`](xarray.DataTree.median.html.md#xarray.DataTree.median)([dim, skipna, keep_attrs]) | Reduce this DataTree's data by applying `median` along some dimension(s). | | [`min`](xarray.DataTree.min.html.md#xarray.DataTree.min)([dim, skipna, keep_attrs]) | Reduce this DataTree's data by applying `min` (i.e., minimum) along some dimension(s). | | [`orphan`](xarray.DataTree.orphan.html.md#xarray.DataTree.orphan)() | Detach this node from its parent. | | [`persist`](xarray.DataTree.persist.html.md#xarray.DataTree.persist)(\*\*kwargs) | Trigger computation, keeping data as chunked arrays. | | [`pipe`](xarray.DataTree.pipe.html.md#xarray.DataTree.pipe)(func, \*args, \*\*kwargs) | Apply `func(self, *args, **kwargs)` | | [`prod`](xarray.DataTree.prod.html.md#xarray.DataTree.prod)([dim, skipna, min_count, keep_attrs]) | Reduce this DataTree's data by applying `prod` (i.e., product) along some dimension(s). | | `prune`([drop_size_zero_vars]) | Remove empty nodes from the tree. | | `reduce`(func[, dim, keep_attrs, keepdims, ...]) | Reduce this tree by applying func along some dimension(s). | | [`relative_to`](xarray.DataTree.relative_to.html.md#xarray.DataTree.relative_to)(other) | Compute the relative path from this node to node other. | | [`round`](xarray.DataTree.round.html.md#xarray.DataTree.round)(\*args, \*\*kwargs) | | | [`same_tree`](xarray.DataTree.same_tree.html.md#xarray.DataTree.same_tree)(other) | True if other node is in the same tree as this node. | | [`sel`](xarray.DataTree.sel.html.md#xarray.DataTree.sel)([indexers, method, tolerance, drop]) | Returns a new data tree with each array indexed by tick labels along the specified dimension(s). | | `set_close`(close) | Set the closer for this node. | | [`std`](xarray.DataTree.std.html.md#xarray.DataTree.std)([dim, skipna, ddof, keep_attrs]) | Reduce this DataTree's data by applying `std` (i.e., standard deviation) along some dimension(s). | | [`sum`](xarray.DataTree.sum.html.md#xarray.DataTree.sum)([dim, skipna, min_count, keep_attrs]) | Reduce this DataTree's data by applying `sum` along some dimension(s). | | [`to_dataset`](xarray.DataTree.to_dataset.html.md#xarray.DataTree.to_dataset)([inherit]) | Return the data in this node as a new xarray.Dataset object. | | [`to_dict`](xarray.DataTree.to_dict.html.md#xarray.DataTree.to_dict)([relative]) | Create a dictionary mapping of paths to the data contained in those nodes. | | [`to_netcdf`](xarray.DataTree.to_netcdf.html.md#xarray.DataTree.to_netcdf)([filepath, mode, encoding, ...]) | Write datatree contents to a netCDF file. | | [`to_zarr`](xarray.DataTree.to_zarr.html.md#xarray.DataTree.to_zarr)(store[, mode, encoding, ...]) | Write datatree contents to a Zarr store. | | [`update`](xarray.DataTree.update.html.md#xarray.DataTree.update)(other) | Update this node's children and / or variables. | | [`values`](xarray.DataTree.values.html.md#xarray.DataTree.values)() | | | [`var`](xarray.DataTree.var.html.md#xarray.DataTree.var)([dim, skipna, ddof, keep_attrs]) | Reduce this DataTree's data by applying `var` (i.e., variance) along some dimension(s). | ### Attributes | [`ancestors`](xarray.DataTree.ancestors.html.md#xarray.DataTree.ancestors) | All parent nodes and their parent nodes, starting with the most distant. | |------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------| | [`attrs`](xarray.DataTree.attrs.html.md#xarray.DataTree.attrs) | Dictionary of global attributes on this node object. | | [`children`](xarray.DataTree.children.html.md#xarray.DataTree.children) | Child nodes of this node, stored under a mapping via their names. | | [`chunksizes`](xarray.DataTree.chunksizes.html.md#xarray.DataTree.chunksizes) | Mapping from group paths to a mapping of chunksizes. | | [`coords`](xarray.DataTree.coords.html.md#xarray.DataTree.coords) | Dictionary of xarray.DataArray objects corresponding to coordinate variables | | [`data_vars`](xarray.DataTree.data_vars.html.md#xarray.DataTree.data_vars) | Dictionary of DataArray objects corresponding to data variables | | [`dataset`](xarray.DataTree.dataset.html.md#xarray.DataTree.dataset) | An immutable Dataset-like view onto the data in this node. | | [`depth`](xarray.DataTree.depth.html.md#xarray.DataTree.depth) | Maximum level of this tree. | | [`descendants`](xarray.DataTree.descendants.html.md#xarray.DataTree.descendants) | Child nodes and all their child nodes. | | [`dims`](xarray.DataTree.dims.html.md#xarray.DataTree.dims) | Mapping from dimension names to lengths. | | [`ds`](xarray.DataTree.ds.html.md#xarray.DataTree.ds) | An immutable Dataset-like view onto the data in this node. | | [`encoding`](xarray.DataTree.encoding.html.md#xarray.DataTree.encoding) | Dictionary of global encoding attributes on this node object. | | [`groups`](xarray.DataTree.groups.html.md#xarray.DataTree.groups) | Return all groups in the tree, given as a tuple of path-like strings. | | [`has_attrs`](xarray.DataTree.has_attrs.html.md#xarray.DataTree.has_attrs) | Whether or not there are any metadata attributes in this node. | | [`has_data`](xarray.DataTree.has_data.html.md#xarray.DataTree.has_data) | Whether or not there are any variables in this node. | | [`indexes`](xarray.DataTree.indexes.html.md#xarray.DataTree.indexes) | Mapping of pandas.Index objects used for label based indexing. | | [`is_empty`](xarray.DataTree.is_empty.html.md#xarray.DataTree.is_empty) | False if node contains any data or attrs. | | [`is_hollow`](xarray.DataTree.is_hollow.html.md#xarray.DataTree.is_hollow) | True if only leaf nodes contain data. | | [`is_leaf`](xarray.DataTree.is_leaf.html.md#xarray.DataTree.is_leaf) | Whether this node is a leaf node. | | [`is_root`](xarray.DataTree.is_root.html.md#xarray.DataTree.is_root) | Whether this node is the tree root. | | [`leaves`](xarray.DataTree.leaves.html.md#xarray.DataTree.leaves) | All leaf nodes. | | [`level`](xarray.DataTree.level.html.md#xarray.DataTree.level) | Level of this node. | | [`lineage`](xarray.DataTree.lineage.html.md#xarray.DataTree.lineage) | All parent nodes and their parent nodes, starting with the closest. | | [`name`](xarray.DataTree.name.html.md#xarray.DataTree.name) | The name of this node. | | [`nbytes`](xarray.DataTree.nbytes.html.md#xarray.DataTree.nbytes) | | | [`parent`](xarray.DataTree.parent.html.md#xarray.DataTree.parent) | Parent of this node. | | [`parents`](xarray.DataTree.parents.html.md#xarray.DataTree.parents) | All parent nodes and their parent nodes, starting with the closest. | | [`path`](xarray.DataTree.path.html.md#xarray.DataTree.path) | Return the file-like path from the root to this node. | | [`root`](xarray.DataTree.root.html.md#xarray.DataTree.root) | Root node of the tree | | [`siblings`](xarray.DataTree.siblings.html.md#xarray.DataTree.siblings) | Nodes with the same parent as this node. | | [`sizes`](xarray.DataTree.sizes.html.md#xarray.DataTree.sizes) | Mapping from dimension names to lengths. | | [`subtree`](xarray.DataTree.subtree.html.md#xarray.DataTree.subtree) | Iterate over all nodes in this tree, including both self and all descendants. | | [`subtree_with_keys`](xarray.DataTree.subtree_with_keys.html.md#xarray.DataTree.subtree_with_keys) | Iterate over relative paths and node pairs for all nodes in this tree. | | [`variables`](xarray.DataTree.variables.html.md#xarray.DataTree.variables) | Low level interface to node contents as dict of Variable objects. | | [`width`](xarray.DataTree.width.html.md#xarray.DataTree.width) | Number of nodes at this level in the tree. | | [`xindexes`](xarray.DataTree.xindexes.html.md#xarray.DataTree.xindexes) | Mapping of xarray Index objects used for label based indexing. |