object

halstead_metric(Stroud)

  • Stroud - Coefficient for computing the time required to program.

Computes Halstead complexity numbers for an entity.

Availability:
logtalk_load(code_metrics(loader))
Author: Paulo Moura
Version: 0:9:0
Date: 2024-03-27
Compilation flags:
static, context_switching_calls
Imports:
public code_metrics_utilities
public code_metric
Uses:
list
numberlist
pairs
Remarks:

  • Definition of operators: Predicates declared, user-defined, and called are interpreted as operators. Built-in predicates and built-in control constructs are ignored.

  • Definition of operands: Predicate arguments are abstracted and interpreted as operands. Note that this definition of operands is a significant deviation from the original definition, which used syntactic literals.

  • Pn: Number of distinct predicates (declared, defined, called, or updated).

  • PAn: Number of predicate arguments (assumed distinct).

  • Cn: Number of predicate calls/updates + number of clauses.

  • CAn: Number of predicate call/update arguments + number of clause head arguments.

  • EV: Entity vocabulary: EV = Pn + PAn.

  • EL: Entity length: EL = Cn + CAn.

  • V: Volume: V = EL * log2(EV).

  • D: Difficulty: D = (Pn/2) * (CAn/An).

  • E: Effort: E = D * V.

  • T: Time required to program: T = E/k seconds (k is the Stroud number; defaults to 18).

  • B: Number of delivered bugs: B = V/3000.

  • Entity score: Represented as the compound term pn_pan_cn_can_ev_el_v_d_e_t_b/11.

Inherited public predicates:
 all/0  all/1  all_score/1  check_option/1  check_options/1  default_option/1  default_options/1  directory/1  directory/2  directory_score/2  entity/1  entity_score/2  file/1  file/2  file_score/2  format_entity_score//2  library/1  library/2  library_score/2  option/2  option/3  rdirectory/1  rdirectory/2  rdirectory_score/2  rlibrary/1  rlibrary/2  rlibrary_score/2  valid_option/1  valid_options/1

Public predicates

(no local declarations; see entity ancestors if any)

Protected predicates

(no local declarations; see entity ancestors if any)

Private predicates

(no local declarations; see entity ancestors if any)

Operators

(none)