blender-manual/manual/modeling/geometry_nodes/utilities/field/evaluate_at_index.rst

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.. index:: Geometry Nodes; Evaluate at Index
.. _bpy.types.GeometryNodeFieldAtIndex:
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Evaluate at Index Node
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.. figure:: /images/node-types_GeometryNodeFieldAtIndex.webp
:align: right
:alt: Evaluate at Index Node.
The *Evaluate at Index* node allows accessing data of other elements in the context geometry.
It is similar to the :doc:`/modeling/geometry_nodes/geometry/sample/sample_index`.
The main difference is that this node does not require a geometry input, because the geometry
from the :ref:`field context <field-context>` is used.
This node is also similar to the :doc:`/modeling/geometry_nodes/utilities/field/evaluate_on_domain` node,
except that the value to retrieve from the specified domain is specified by an index rather than
an automatic domain interpolation.
Inputs
======
Index
The :doc:`index </modeling/geometry_nodes/geometry/read/input_index>` of the element in the selected domain
to retrieve data from, i.e. "the fourth face", or "the first control point".
Value
The field to retrieve data from.
Properties
==========
Domain
The :ref:`attribute domain <attribute-domains>` used for evaluation of the *Value* input.
This is useful because it can be a different domain than the domain from the
:ref:`field context <field-context>`, i.e. to choose a vertex for each face.
Output
======
Value
The value of the input field at the given index.