tree

The Deephaven tree method creates a tree table from a source table given an ID column name and parent column name.

Syntax

source.tree(id_col: str, parent_col: str, promote_orphans: bool = False) -> TreeTable

Parameters

Parameter	Type	Description
id_col	str	The name of the ID column.
parent_col	str	The name of the parent column.
promote_orphans optional	bool	Whether to promote node tables whose parents do not exist to be children of the root node. The default is `False`.

Returns

A tree table.

Examples

The following example creates a tree table from a static table.

from deephaven.constants import NULL_INT
from deephaven import empty_table

source = empty_table(100).update_view(
    ["ID = i", "Parent = i == 0 ? NULL_INT : (int)(i / 4)"]
)

result = source.tree(id_col="ID", parent_col="Parent")

The following example creates a tree table from a real-time table.

from deephaven import empty_table, time_table
from deephaven.constants import NULL_INT

t1 = empty_table(10_000).update_view(
    ["ID = i", "Parent = i == 0 ? NULL_INT : (int)(i / 10)"]
)
t2 = time_table("PT0.01S").update_view(["I = i % 10_000"]).last_by("I")

source = t1.join(t2, "ID = I")

result = source.tree(id_col="ID", parent_col="Parent")

A user navigates between the source table and result tree table

The following example creates a tree table from a source table that contains orphans. The first omits orphan nodes, while the second promotes them such that they appear in the tree table.

from deephaven.constants import NULL_INT
from deephaven import empty_table

source = empty_table(100).update_view(
    ["ID = i + 2", "Parent = i == 0 ? NULL_INT : i % 9"]
)

result_no_orphans = source.tree(id_col="ID", parent_col="Parent")
result_w_orphans = source.tree(id_col="ID", parent_col="Parent", promote_orphans=True)

tree

Syntax

Parameters

Returns

Examples

Related documentation