pub trait FeatureFunction: Send + Sync {
// Required methods
fn compute(
&self,
prev_label: Option<usize>,
curr_label: usize,
input_sequence: &[usize],
position: usize,
) -> f64;
fn name(&self) -> &str;
}Expand description
Feature function for linear-chain CRF.
Features can be:
- Transition features: depend on (yᵢ₋₁, yᵢ, x, i)
- Emission features: depend on (yᵢ, x, i)
Required Methods§
Sourcefn compute(
&self,
prev_label: Option<usize>,
curr_label: usize,
input_sequence: &[usize],
position: usize,
) -> f64
fn compute( &self, prev_label: Option<usize>, curr_label: usize, input_sequence: &[usize], position: usize, ) -> f64
Compute feature value for a transition.
§Arguments
prev_label- Previous output label (None for first position)curr_label- Current output labelinput_sequence- Input sequenceposition- Current position in sequence