> ## Documentation Index
> Fetch the complete documentation index at: https://docs.activeviam.com/llms.txt
> Use this file to discover all available pages before exploring further.

# atoti.Level

### *final class* atoti.Level

Level of a [`Hierarchy`](./atoti.hierarchy#atoti.Hierarchy).

A level is a sub category of a hierarchy.
Levels have a specific order with a parent-child relationship.

In a Pivot Table, a single-level hierarchy will be displayed as a flat attribute while a multi-level hierarchy will display the first level and allow users to expand each member against the next level and display sub totals.

For example, a Geography hierarchy can have a Continent as the top level where Continent expands to Country which in turn expands to the leaf level: City.

| [`data_type`](./atoti.Level.data_type#atoti.Level.data_type) | Type of the level members.                                                                                                                         |
| ------------------------------------------------------------ | -------------------------------------------------------------------------------------------------------------------------------------------------- |
| [`dimension`](./atoti.Level.dimension#atoti.Level.dimension) | Name of the dimension holding the level.                                                                                                           |
| [`hierarchy`](./atoti.Level.hierarchy#atoti.Level.hierarchy) | Name of the hierarchy holding the level.                                                                                                           |
| [`isin`](./atoti.Level.isin#atoti.Level.isin)                | Return a condition evaluating to `True` where this level's current member is included in the given *members*, and evaluating to `False` elsewhere. |
| [`isnull`](./atoti.Level.isnull#atoti.Level.isnull)          | Return a condition evaluating to `True` where this level is not expressed, and evaluating to `False` elsewhere.                                    |
| [`name`](./atoti.Level.name#atoti.Level.name)                | Name of the level.                                                                                                                                 |
| [`order`](./atoti.Level.order#atoti.Level.order)             | Order in which to sort the level's members.                                                                                                        |