--- title: "mlab-builtins-mod-dimensions — Mova code model" description: "Mova code model of mlab/src/builtins/mod.rs: components with their labels, obernants and the model text." url: "https://groupants.elamur.ai/free/en/mova/mlab/src/builtins/mod.rs.groupant/dimensions.groupant/" --- Elamur: [Mova](https://md.mova.elamur.ai/free/en/) · [Dictionary](https://md.dictionary.elamur.ai/free/en/) · [Research](https://md.research.elamur.ai/free/en/) · **Groupants** This page as HTML: # mlab-builtins-mod-dimensions The groupant beside mlab/src/builtins/mod.rs in the Mova repository: what the code computes, what it never does, how to go back from its outputs, its invariants, cost and checks. ## Facts - **kind:** groupant_fragment - **status:** partial source bound model - **source:** [`mlab/src/builtins/mod.rs`](https://github.com/ElamurAI/mova-free/blob/main/mlab/src/builtins/mod.rs) - **source SHA-256:** `5e593db042fb0f9c…` - **covers:** Filter char values, dispatch by numeric argument count, map dimensions with NaN rejection then clamp/floor/saturating cast; constrain higher dimensions to one. (bytes 3299–5008) - **part of:** [mlab-builtins-mod](https://md.groupants.elamur.ai/free/en/mova/mlab/src/builtins/mod.rs.groupant/) - **repository folder:** [`mlab/src/builtins/mod.rs.groupant/dimensions.groupant`](https://github.com/ElamurAI/mova-free/tree/main/mlab/src/builtins/mod.rs.groupant/dimensions.groupant) - **repository commit:** `48f2e6f74146` > **Implementation material.** A Mova code model describes this code at one source revision: partial models, finite checks and their stated scope. It is not a reviewed general exposition, and its labels are shown as written, never raised. ## Components | component | label | where | |---|---|---| | **approximant** | partial | [approximant](#approximant) | | **ast** | partial | `../syntax.json` | | **cost** | symbolic source derived | [invariant](#invariant) | | **descriptant** | present | [descriptant](#descriptant) | | **invariant** | partial | [invariant](#invariant) | | **tests** | executed bounded checks | [tests](#tests) | ## Obernants The typed relations around the forward model: the behaviour complement (what the code never does), the reverse reconstruction (every input compatible with an output) and specialised views. | id | type | label | where | |---|---|---|---| | `behavior_complement` | behavior_complement | partial source derived model | [behavior_complement](#behavior-complement) | | `reverse_reconstruction` | reverse_reconstruction | partial source derived model | [reverse_reconstruction](#reverse-reconstruction) | | `state_invariant` | state_invariant | partial source derived model | [state_invariant](#state-invariant) | | `failure_precedence` | failure_precedence | partial source derived model | [failure_precedence](#failure-precedence) | | `representation_transport` | representation_transport | partial source derived model | [representation_transport](#representation-transport) | | `resource_cost` | resource_cost | partial source derived model | [resource_cost](#resource-cost) | ## Model text ### descriptant #### mlab-builtins-mod-dimensions Filter char values, dispatch by numeric argument count, map dimensions with NaN rejection then clamp/floor/saturating cast; constrain higher dimensions to one. ##### Modeling epoch — 2026-10-31 Prospective source read preceded edits. Bounded synthetic checks and selected existing safe tests exercise actual code; paired debug/release results and compiled negative-control assertions are retained externally. Frozen scenario, corpus, external measurement, full-school and training effects are unexecuted. Partial lexical syntax supplies no macro-expanded or semantic proof. ### approximant #### Forward relation Filter char values, dispatch by numeric argument count, map dimensions with NaN rejection then clamp/floor/saturating cast; constrain higher dimensions to one. ##### Domain Valid Rust value/storage invariants and available bounded resources; exact branch and effect observations only. ##### Executable approximant gap No useful percentage-error surrogate is established for these categorical, textual or effectful observations. Supported future caps are 1%, 2%, 5%, 10%; no executable approximation or production substitution is claimed. ### invariant #### Invariants and costs The helper returns a pair only and does not allocate the requested matrix. ##### Failure ordering Nonscalar multiargument input is Invalid call; one vector with >2 elements rejects any raw trailing value not exactly 1. ##### Cost O(number of supplied values and inspected dimensions); input Mat invariants assumed. ### models ## Typed models — mlab-builtins-mod-dimensions Source-derived partial relations; finite checks do not prove universality. ### behavior_complement Negative dimensions exclude negative output sizes. More than two nonunit trailing dimensions exclude successful 2D shape. ### reverse_reconstruction (2,2) admits scalar 2.9, vector [2,2], two scalar args 2 and 2 plus skipped class strings; shape does not identify original arity. ### state_invariant The helper returns a pair only and does not allocate the requested matrix. ### failure_precedence Nonscalar multiargument input is Invalid call; one vector with >2 elements rejects any raw trailing value not exactly 1. ### representation_transport Empty numeric vector maps 0x0 whereas absent numeric arguments maps 1x1. ### resource_cost O(number of supplied values and inspected dimensions); input Mat invariants assumed. ### tests #### Evidence and limitations Parent source checks: builtins::wave30_tests::registry_and_dimensions. The fragment's actual statements lie in the recorded byte range; parent checks need not exercise every branch in this fragment. See ../tests.md for source-level control and limitations. AST projection generated twice to fresh files and compared byte-for-byte. Runtime evidence is finite and does not establish every branch, allocation failure, backend implementation or effect path. No optimization or speed claim.