v0.4.0 - add list of tree tuples

Author: kayjan

CHANGELOG.md

@@ -8,6 +8,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Work In Progress
 - Node: WeightedNode for weighted edge tree implementation.
 
+## [0.4.0] - 2022-11-07
+### Added
+- Tree Constructors: From list of tuples of parent-child.
+
 ## [0.3.3] - 2022-11-07
 ### Added
 - DAG Exporter: To list, nested dictionary, pandas DataFrame.
@@ -51,6 +55,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Utility Iterators: Tree traversal methods.
 - Workflow To Do App: Tree use case with to-do list implementation.
 
+[0.4.0]: https://github.com/kayjan/bigtree/compare/v0.3.3...v0.4.0
 [0.3.3]: https://github.com/kayjan/bigtree/compare/v0.3.2...v0.3.3
 [0.3.2]: https://github.com/kayjan/bigtree/compare/v0.3.1...v0.3.2
 [0.3.1]: https://github.com/kayjan/bigtree/compare/v0.3.0...v0.3.1

README.md

@@ -20,12 +20,13 @@ For Tree implementation, there are 8 main components.
    2. ``Node``, BaseNode with node name attribute
 2. **Constructing Tree**
    1. From *list*, containing paths
-   2. From *nested dictionary*
-   3. From *nested recursive dictionary*
-   4. From *pandas DataFrame*
-   5. Add nodes to existing tree using list
-   6. Add nodes and attributes to existing tree using dictionary or pandas DataFrame, add using path
-   7. Add only attributes to existing tree using dictionary or pandas DataFrame, add using name
+   2. From *list*, containing parent-child tuples
+   3. From *nested dictionary*
+   4. From *nested recursive dictionary*
+   5. From *pandas DataFrame*
+   6. Add nodes to existing tree using list
+   7. Add nodes and attributes to existing tree using dictionary or pandas DataFrame, add using path
+   8. Add only attributes to existing tree using dictionary or pandas DataFrame, add using name
 3. **Traversing Tree**
    1. Pre-Order Traversal
    2. Post-Order Traversal
@@ -163,13 +164,20 @@ print_tree(root, style="ascii")
 
 2. **From *list***
 
-Construct nodes only, list contains full paths of nodes.
+Construct nodes only, list contains full paths of nodes or tuples of parent-child names.
 
 ```python
-from bigtree import list_to_tree, print_tree
+from bigtree import list_to_tree, list_to_tree_tuples, print_tree
 
 root = list_to_tree(["a/b/d", "a/c"])
 
+print_tree(root)
+# a
+# |-- b
+# |   `-- d
+# `-- c
+
+root = list_to_tree_tuples([("a", "b"), ("a", "c"), ("b", "d")])
 print_tree(root)
 # a
 # |-- b

bigtree/__init__.py

@@ -1,4 +1,4 @@
-__version__ = "0.3.3"
+__version__ = "0.4.0"
 
 from bigtree.dag.construct import dataframe_to_dag, dict_to_dag, list_to_dag
 from bigtree.dag.export import dag_to_dataframe, dag_to_dict, dag_to_dot, dag_to_list
@@ -14,6 +14,7 @@
     dataframe_to_tree,
     dict_to_tree,
     list_to_tree,
+    list_to_tree_tuples,
     nested_dict_to_tree,
 )
 from bigtree.tree.export import (

bigtree/tree/construct.py

@@ -1,5 +1,5 @@
 from collections import OrderedDict
-from typing import Type
+from typing import List, Tuple, Type
 
 import pandas as pd
 
@@ -14,6 +14,7 @@
     "add_dict_to_tree_by_name",
     "add_dataframe_to_tree_by_path",
     "add_dataframe_to_tree_by_name",
+    "list_to_tree_tuples",
     "list_to_tree",
     "dict_to_tree",
     "nested_dict_to_tree",
@@ -402,6 +403,49 @@ def add_dataframe_to_tree_by_name(
     )
 
 
+def list_to_tree_tuples(
+    relations: List[Tuple[str, str]],
+    node_type: Type[Node] = Node,
+) -> Node:
+    """Construct tree from list of tuple containing parent-child names.
+
+    >>> from bigtree import list_to_tree_tuples, print_tree
+    >>> relations_list = [("a", "b"), ("a", "c"), ("b", "d"), ("b", "e"), ("c", "f"), ("e", "g"), ("e", "h")]
+    >>> root = list_to_tree_tuples(relations_list)
+    >>> print_tree(root)
+    a
+    |-- b
+    |   |-- d
+    |   `-- e
+    |       |-- g
+    |       `-- h
+    `-- c
+        `-- f
+
+    Args:
+        relations (list): list containing tuple containing parent-child names
+        node_type (Type[Node]): node type of tree to be created, defaults to Node
+
+    Returns:
+        (Node)
+    """
+    if not len(relations):
+        raise ValueError("Path list does not contain any data, check `relations`")
+
+    node_dict = {}
+    for parent_name, child_name in relations:
+        if not node_dict.get(parent_name):
+            node_dict[parent_name] = node_type(parent_name)
+        if not node_dict.get(child_name):
+            node_dict[child_name] = node_type(child_name)
+
+        parent_node = node_dict[parent_name]
+        child_node = node_dict[child_name]
+        child_node.parent = parent_node
+    root = child_node.root
+    return root
+
+
 def list_to_tree(
     paths: list,
     sep: str = "/",

tests/tree/test_construct.py

@@ -14,6 +14,7 @@
     dataframe_to_tree,
     dict_to_tree,
     list_to_tree,
+    list_to_tree_tuples,
     nested_dict_to_tree,
 )
 from bigtree.utils.exceptions import DuplicatedNodeError, TreeError
@@ -825,6 +826,47 @@ def test_add_dataframe_to_tree_by_name_duplicate_node(self):
         assert_tree_structure_basenode_root_attr(root)
 
 
+class TestListToTreeTuples(unittest.TestCase):
+    def setUp(self):
+        """
+        Tree should have structure
+        a
+        |-- b
+        |   |-- d
+        |   +-- e
+        |       |-- g
+        |       +-- h
+        +-- c
+            +-- f
+        """
+        self.relations = [
+            ("a", "b"),
+            ("a", "c"),
+            ("b", "d"),
+            ("b", "e"),
+            ("c", "f"),
+            ("e", "g"),
+            ("e", "h"),
+        ]
+
+    def tearDown(self):
+        self.relations = None
+
+    def test_list_to_tree_tuples(self):
+        root = list_to_tree_tuples(self.relations)
+        assert_tree_structure_basenode_root_generic(root)
+        assert_tree_structure_node_root_generic(root)
+
+    def test_list_to_tree_tuples_reversed(self):
+        root = list_to_tree_tuples(self.relations[::-1])
+        assert_tree_structure_basenode_root_generic(root)
+        assert_tree_structure_node_root_generic(root)
+
+    def test_list_to_tree_tuples_empty(self):
+        with pytest.raises(ValueError):
+            list_to_tree_tuples([])
+
+
 class TestListToTree(unittest.TestCase):
     def setUp(self):
         """