Glossary ======== This page collects the **formal terms** used by the Extended Matrix language. Each entry points back to the main chapter that defines the concept in detail; this glossary is meant as a quick-lookup reference, not as a substitute for the chapters themselves. .. note:: **Editors:** keep entries short (1–3 sentences). The canonical definition lives in the linked chapter — this page only restates the gist and points there. .. glossary:: :sorted: Extended Matrix (EM) EM The formal language for documenting stratigraphy and virtual reconstruction processes in cultural heritage. Defined as a typed visual notation drawable in yEd or producible programmatically via :term:`s3Dgraphy`. See :doc:`stratigraphic_approach`. Extended Matrix Framework (EMF) The set of open-source software tools that operationalise the EM language: the :term:`yEd palette`, :term:`EM Tools for Blender`, :term:`3DSC`, :term:`Heriverse` and the :term:`s3Dgraphy` library that holds them together. See the `framework overview `__. Extended Matrix Ecosystem The combined whole of the formal language and its toolset: :term:`EM` (the language) together with the :term:`Extended Matrix Framework (EMF)` (the open-source toolset that operationalises it — :term:`yEd palette`, :term:`EM Tools for Blender`, :term:`s3Dgraphy`, :term:`Heriverse`, :term:`3DSC`). Used when you need to refer to the entire EM-aware stack as a single thing. EM Tools for Blender EM Tools The open-source Blender add-on that connects an :term:`EM graph` to 3D content inside Blender — browse stratigraphic units, link proxies, drive visualisation by epoch and property, export to :term:`Heriverse` and CSV. Part of the :term:`Extended Matrix Framework (EMF)`. See the `EM Tools manual `__. 3DSC 3D Survey Collection — the open-source Blender add-on (with a companion Metashape pipeline) for managing photogrammetric and 3D survey data: level-of-detail handling, texture baking, and asset preparation ready to be linked to an :term:`EM graph`. Part of the :term:`Extended Matrix Framework (EMF)`. See the `3DSC documentation `__. yEd palette The palette of EM-typed nodes and arcs that turns yEd (a free graph editor) into an :term:`EM graph` authoring tool. The starting point for anyone drawing an EM by hand. Part of the :term:`Extended Matrix Framework (EMF)`. Stratigraphic Unit (US) The basic unit of archaeological stratigraphy: a discrete physical entity (a layer, a wall, a cut) recorded during excavation. EM extends this with virtual variants — see :doc:`stratigraphic_nodes`. Virtual Stratigraphic Unit (USV) A stratigraphic unit whose physical evidence is partial or absent and whose existence is inferred. Comes in two flavours — :term:`USVs` (with an in-situ anchor) and :term:`USVn` (pure typology). See :doc:`stratigraphic_nodes`. USVs A Virtual Stratigraphic Unit anchored to an in-situ archaeological remain. The anchor connects the inference back to tangible evidence. See :doc:`stratigraphic_nodes`. USVn A Virtual Stratigraphic Unit defined purely by typology — no in-situ anchor, the unit is reconstructed from comparanda and type-based reasoning. See :doc:`stratigraphic_nodes`. USD A Documented Stratigraphic Unit — a unit attested by bibliographic, archival or iconographic documentation rather than by direct excavation. See :doc:`stratigraphic_nodes`. Special Find (SF) A discrete object found in a stratigraphic unit, recorded as a separate entity (e.g. an inscription, a coin). See :doc:`auxiliary_stratigraphic_nodes`. Virtual Special Find (VSF) A nodegroup containing :term:`SF ` fragments that have been reconstructed virtually. The VSF is a *container*, not a single reconstructed object. See :doc:`auxiliary_stratigraphic_nodes`. Transformation Stratigraphic Unit (TSU) A node type introduced in EM 1.4 (and refined in 1.5) for documenting *states* and *transformations* — decay, restoration, thematic surveys — rather than the original construction events. Property (Qualia) A typed paradata attribute attached to a stratigraphic unit — a measurable or qualitative value (length, material, dating, construction technique). Connected upstream to the :term:`Extractor` and :term:`Combiner` nodes that justify the value. See :doc:`qualia` and :doc:`paradata_nodes`. Document A primary source — a survey drawing, a photograph, a manuscript, a publication — referenced by an :term:`Extractor` to derive a :term:`Property (Qualia)`. See :doc:`source_node`. Extractor A paradata node representing the *act of extraction* of an attribute from a :term:`Document`. Materialises the "from-source-to-property" reasoning step. See :doc:`extractor_nodes`. Combiner A paradata node that *combines* multiple extractor outputs into a single :term:`Property (Qualia)` value, typically when a single value cannot be derived from a single source. See :doc:`paradata_group`. Paradata The reasoning that connects sources to interpretive results: what was used, how it was used, and what was concluded. Mandatory in EM — every reconstructive node must be backed by a paradata chain. See :doc:`paradata_nodes`. Activity An Activity Node Group — a set of stratigraphic units linked by a common operation (e.g. "construction of the apse"). See :doc:`activity`. Epoch A named time horizon used to attribute and filter stratigraphic units (``has_first_epoch`` / ``has_last_epoch``). It is the temporal counterpart of a *swimlane* in the :term:`Canvas` — every node that belongs to that period is contained within its swimlane, which acts as the visual home of the epoch in the :term:`EM graph`. Epochs are not stratigraphic units themselves; they are the calendar against which units are placed. See :doc:`canvas`. Canvas The yEd surface where the :term:`EM graph` is authored. Carries the metadata used by the framework — site code, epoch palette, author, licence — typically inside an ``SL_PD`` nodegroup, and organises nodes by :term:`Epoch` through swimlanes. See :doc:`canvas`. EM graph The **visual notation** of an Extended Matrix — the typed nodes and arcs as drawn on paper, in yEd with the :term:`yEd palette`, or produced by AI-extraction workflows. The human-readable face of EM. Distinct from the in-memory :term:`S3D Graph` that :term:`s3Dgraphy` builds from it. Knowledge Graph The underlying property graph encoded by an :term:`EM graph`, made programmatically accessible via :term:`s3Dgraphy` as an :term:`S3D Graph`. See :doc:`knowledge_tree`. s3Dgraphy The open-source Python library that handles the mapping between tool-specific data formats (GraphML, JSON, XLSX) and the Stratigraphic :term:`Knowledge Graph`. It is the *package* — the runtime artifact it produces is the :term:`S3D Graph`. Used by every framework component (:term:`EM Tools for Blender`, :term:`Heriverse`, :term:`3DSC`) for any programmatic access to EM data. See the index page of this manual. *See also:* a long-term perspective for this work, if it grows into a formalisation of CIDOC-CRM for 3D stratigraphy and virtual reconstruction, is the working name **CRM-s3D** (not currently in use; mentioned here for forward reference only). pyArchInit An open-source `QGIS `_ plugin for archaeological data management, with particular strength in 2D GIS visualization of stratigraphic data. Maintained by an active community led by Luca Mandolesi. In the Extended Matrix ecosystem, pyArchInit projects are consumed through the `s3Dgraphy `_ library, either by reference or by baking their records into the EM graph. See the :doc:`cookbook/pyarchinit_integration` recipe for the integration workflow and the :doc:`ecosystem` registry entry. S3D Graph The **in-memory property graph** produced by :term:`s3Dgraphy`. It is the runtime data structure with all methods for reading, writing and querying stratigraphic relationships, and is serialisable to JSON. Distinct from the visual notation (:term:`EM graph`) which is the human-readable face — the S3D Graph is the machine-processable face of the same knowledge. Heriverse The web-based publication platform of the EM Framework — turns :term:`EM graphs ` and 3D content into navigable, paradata-aware online experiences. The public product name; the underlying conceptual model is :term:`StratiVerse` (used in academic papers and internal manuals). See the `Heriverse documentation `__. StratiVerse The conceptual model that underlies the :term:`Heriverse` product. Referenced in academic papers and internal manuals; the public tool name is **Heriverse**. .. note:: **Editors:** when you add a new term, place its short definition here and link to the chapter where the full discussion lives. Avoid redefining concepts in two places — the chapter is authoritative; the glossary entry is the lookup.