IvfPqIndex class

IVF cell-probe + PQ residual compression. Requires train(...) before add(...) (trains coarse quantizer and PQ codebooks in sequence). Ranks in approximate squared L2 always — the metric argument to search is accepted for API symmetry but ignored.

Constructors

IvfPqIndex(int dim, {required int nlist, required int m, int nprobe = 1, int seed = 1234, int niter = 25})

Properties

dim → int
final
hashCode → int
The hash code for this object.
no setterinherited
isTrained → bool
no setter
length → int
no setter
liveIds → Iterable<Object?>
V50: snapshot of all ids across every cell.
no setter
m → int
final
nlist → int
final
nprobe ↔ int
getter/setter pair
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

Methods

add(Object? id, Vector v) → void
Add v under key id. Assigns to nearest cell, encodes its residual, appends the PQ code.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
removeId(Object? id) → bool
Remove the first entry whose id equals id. Walks all cells.
Top-k nearest neighbors of query. Per-call nprobe overrides the field.
toJson() → Map<String, Object?>
Serialize coarse centroids + PQ codebooks + every populated cell.
toString() → String
A string representation of this object.
inherited
train(List<Vector> samples) → void
Train coarse quantizer + PQ codebooks on residuals.

Operators

operator ==(Object other) → bool
The equality operator.
inherited

Static Methods

fromJson(Map<String, Object?> j) → IvfPqIndex
Reconstruct an IvfPqIndex from toJson output.