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sparsemap_explicit

fynch::sparsemap

Function sparsemap_explicit 

Source 
pub fn sparsemap_explicit(
    theta: &[f64],
    vertices: &[Vec<f64>],
) -> Result<SparseMapPrediction>
Expand description

Compute SparseMAP over an explicit list of vertices.

Given scores theta and vertices v_j, this solves:

argmax_mu <theta, mu> - 0.5 ||mu||^2
  where mu is in conv({v_j})

Equivalently, it projects theta onto the convex hull of the supplied vertices. For standard-basis vertices this recovers sparsemax.

The explicit implementation is bounded to small domains (MAX_EXPLICIT_VERTICES) because it is the seed prototype for the structured-oracle API, not a graph or sequence decoder.

ยงErrors

Returns Error::EmptyInput when theta or vertices is empty, Error::LengthMismatch when a vertex has the wrong dimension, and Error::InvalidWeights when values are non-finite or the explicit vertex limit is exceeded.