Direct measure functions

Each module under zadu.measures exposes a measure() function. Signatures differ: some require both spaces, while others require only a projection and labels. This example uses the arrays from the quickstart:

from zadu.measures import mean_relative_rank_error, neighborhood_hit, pearson_r

mrre = mean_relative_rank_error.measure(original, projection, k=20)
pearson = pearson_r.measure(original, projection)
hit = neighborhood_hit.measure(projection, labels, k=20)

For the same parameters and distance definitions, direct calls compute the same scores as the runner. Functions with return_local=True return a (global_dict, local_dict) tuple. Other functions return a score dictionary; Gap Index also offers a regional API.

Some functions accept precomputed distances or neighbors. They must describe the same samples, row order, distance definition, and neighbor convention as the calculation. Prefer the runner when combining measures so these resources are shared consistently. Typed reduction arguments such as pair_statistics and rank_comparisons are engine interfaces and normally remain unset.

A direct call does not use a runner's memory budget. It can allocate dense distance or rank matrices even if the equivalent scheduled calculation uses blocks. See Memory and execution.

Module mapping

Alias	Module
tnc	trustworthiness_continuity
mrre	mean_relative_rank_error
lcmc	local_continuity_meta_criteria
nh	neighborhood_hit
ca_tnc	class_aware_trustworthiness_continuity
l_tnc	label_trustworthiness_and_continuity
nd	neighbor_dissimilarity
dtm	distance_to_measure
kl_div	kl_divergence
dsc	distance_consistency
pr	pearson_r
srho	spearman_rho
ivm	internal_validation_measure
c_evm	clustering_and_external_validation_measure
snc	steadiness_cohesiveness
topo	topographic_product
proc	procrustes
stress	stress
sn_stress	scale_normalized_stress
nm_stress	non_metric_stress
cadi	class_angular_distortion_index
gi	gap_index

Import modules explicitly in reusable code instead of using a wildcard import. Parameters and return keys are collected in the measure reference.