Lessons Learnt from Gauging Software Metrics of Cabin Software in a Commercial Airliner

Table 4

Results overview.

Metric	Recommended	Worst	Mean	Std. Dev.	Median	Within Rec.	Remarkable modules
Lines of code	—	72,300	7,901	10,527	4,925	—	5, 71
Number of modules	—	71	16	15	10	—	5, 71, 67
Functions per module		1,113		111	58
Halstead length	—	70,000	2,845	8,257	9,493	—
Amount of comments	≥0.5	0.25	0.82	0.37	0.72	81%	1, 19, 46
Functions (per file)	7 ± 2	242	7	5,34	6	71%	5, 22, 48
Vocabulary size	—	2,245	445	354	358	—	—
Difficulty	<30	2,324	186.5	143	152	2.8%	5, 71, 61
Volume	100–8000	667 K	20,697	78,183	9,053	46%	25, 71
Effort	—	4,516 Billion	69.50	531 M	2.3 M	—	25, 71
Size of statements	≤7	46	2.99	7.92	0.90	95%	19, 27, 49, 50
Fan-In	≤7	1,476	196	215	136	0%	5, 66
Fan-out	≤7	3,701	195	443	105	0%	5, 66
Cyclomatic complexity	0–10	383	5.74	51	30	45%	5, 31, 33, ≥57
Nesting	0–5	12	7.2	2.4	7	59%	53, 6, 2
GOTOs	0	0	0	0	0	100%	—
Frequency	—	101	0.08	11.68	3.85	—	26
Coupling (out)	—	235	44	41	38	—	5, 67, 68
Coupling (in)	—	294	41	47	29	—	5, 67,68
Entry nodes	7,951	—	112	207	—	—	—
Exit nodes (per function)	5,618	—	3.34	—	—	—	—