---
title: "Vector"
description: "a vector from a model that carries meaning, named by its model; never a hash"
section: concepts
address: /concepts/vector
contract: 0476e35e6e275db5
---

# Vector

a vector from a model that carries meaning, named by its model; never a hash

[figure: Vector is a fact at follows scope. The drawing shows its fields and the objects that they point at.]

| property | value |
|---|---|
| kind | fact |
| scope | follows |
| key | the hash of the text, the model and the tier |
| store | postgres+lake |
| family | record |



## Fields


| field | type | required | note |
|---|---|---|---|
| `text_hash` | `hash` | yes |  |
| `model` | [Model](/concepts/model) | yes | a model whose row is ready |
| `tier` | `one of narrow \| wide` | yes |  |
| `width` | `count` | yes |  |
| `numbers` | `[number]` | yes | the vector's numbers at the model's width; the gold column keeps them at one byte a number for the narrow tier and at full precision for the wide, and the wire always carries the numbers |
| `centroid` | `count` | no | the centroid of the coarse index |
| `sketch` | `[count]` | no | the one-bit sketch for the first pass, as 64-bit words; its width is the parameter |
| `media_hash` | `hash` | no | for a vector of an image, a frame or a sound, in place of the text's hash |
| `unit` | `id` | no | the unit whose text was given meaning, when the text is one unit's: an entity, a content item, an observation |



## Routes that use it
No route takes or returns Vector directly. The record holds it, and the objects that point at it reach it.