DataViz.Layout.Hierarchy.Core

hierarchy :: forall a. a -> (a -> Maybe (Array a)) -> HierarchyNode a

Construct a hierarchy from user data Matches D3's hierarchy() function

Simplified implementation using recursion instead of D3's iterative approach This is more idiomatic for PureScript while producing identical results

getHeight :: forall a. HierarchyNode a -> Int

sum :: forall a. HierarchyNode a -> (a -> Number) -> ValuedNode a

Compute aggregate values bottom-up Matches D3's .sum() method

Formula: node.value = value(node.data) + Σ(child.value)

count :: forall a. HierarchyNode a -> ValuedNode a

Count descendants Matches D3's .count() method

Formula:

• Leaf: value = 1
• Internal: value = Σ(child.value)

eachBefore :: forall a b. (HierarchyNode a -> b) -> HierarchyNode a -> Array b

Pre-order traversal (visit parent before children) Matches D3's .eachBefore() method

Order: root → A → A1 → A2 → B → B1 → B2

eachAfter :: forall a b. (HierarchyNode a -> b) -> HierarchyNode a -> Array b

Post-order traversal (visit children before parent) Matches D3's .eachAfter() method

Order: A1 → A2 → A → B1 → B2 → B → root

descendants :: forall a. HierarchyNode a -> Array (HierarchyNode a)

Get all descendant nodes (including self) Matches D3's .descendants() method

leaves :: forall a. HierarchyNode a -> Array (HierarchyNode a)

Get all leaf nodes (nodes with no children) Matches D3's .leaves() method

sortHierarchy :: forall a. (HierarchyNode a -> HierarchyNode a -> Ordering) -> HierarchyNode a -> HierarchyNode a

Sort children by comparator Matches D3's .sort() method

Note: This returns a new hierarchy (pure function)