DIA 5-step drill for any diagram (no internet needed)

1. Open Dia. Left panel drop-down: UML (use case, class, activity, state) or Flowchart + Gane and Sarson (DFD, flow graph)
2. Click a shape, click on the page, double-click it to type the text / fill attributes and operations
3. Connect with the Line tool (top toolbox) or UML Association / Generalization / Dependency / Transition; ends turn red when connected
4. Arrow heads: bottom-left arrow selector or double-click the line > Start / End arrow. Labels: T (Text) tool
5. File > Save (.dia) and File > Export > PNG. Write name, roll no, date on the printout

LMS Library Management System

Members search, reserve, borrow and return books; the librarian issues / returns books and manages books and members; fine is charged for late return.

Actors: Member, Librarian (Admin optional). Classes: Person, Member, Librarian, Book, Loan, Fine.

Viva

OCS Online Course System

Instructors create courses and upload lectures, admin approves, students pay and enroll, watch lectures, take quizzes and download certificates.

Actors: Student, Instructor, Admin, Payment Gateway. Classes: User, Student, Instructor, Course, Lecture, Enrollment, Payment, Quiz.

Viva

CC Cyclomatic complexity (white box)

1. Number every statement / condition (merge simple sequential statements into one node)
2. Draw the flow graph (circles + arrows)
3. Count E, N, P and find V(G) by all 3 methods (they must match)
4. Write V(G) independent paths
5. One test case per path: input, expected, actual, pass / fail

Program 1: largest of three numbers (nested if)

def largest(a, b, c):
    if a > b:              # node 2
        if a > c:          # node 3
            m = a          # node 4
        else:
            m = c          # node 5
    else:
        if b > c:          # node 6
            m = b          # node 7
        else:
            m = c          # node 8
    return m               # node 9

tests = [("TC1", 5, 3, 2, 5), ("TC2", 5, 3, 7, 7), ("TC3", 2, 6, 3, 6), ("TC4", 2, 6, 9, 9)]
for tc, a, b, c, exp in tests:
    got = largest(a, b, c)
    print(tc, (a, b, c), "expected", exp, "actual", got, "PASS" if got == exp else "FAIL")

E = 11, N = 9, predicate nodes P = 3 (2, 3, 6) > V(G) = 11 - 9 + 2 = 4 = P + 1 = 4 = regions 4

Program 2: sum of even numbers 1..n (while loop)

def even_sum(n):
    i, s = 1, 0            # node 1
    while i <= n:          # node 2
        if i % 2 == 0:     # node 3
            s = s + i      # node 4
        i = i + 1          # node 5
    return s               # node 6

tests = [("TC1", 0, 0), ("TC2", 1, 0), ("TC3", 4, 6)]
for tc, n, exp in tests:
    got = even_sum(n)
    print(tc, "n =", n, "expected", exp, "actual", got, "PASS" if got == exp else "FAIL")

E = 7, N = 6, P = 2 (2, 3) > V(G) = 7 - 6 + 2 = 3 = P + 1 = 3. A loop is one decision.

Program 3: binary search

def binary_search(a, key):
    low, high = 0, len(a) - 1      # node 1
    while low <= high:             # node 2
        mid = (low + high) // 2    # node 3
        if a[mid] == key:          # node 4
            return mid             # node 5
        elif key < a[mid]:         # node 6
            high = mid - 1         # node 7
        else:
            low = mid + 1          # node 8
    return -1                      # node 9  (node 10 = end)

tests = [("TC1", [], 5, -1), ("TC2", [1, 3, 5], 3, 1), ("TC3", [3], 1, -1), ("TC4", [3], 7, -1)]
for tc, a, k, exp in tests:
    got = binary_search(a, k)
    print(tc, a, "key", k, "expected", exp, "actual", got, "PASS" if got == exp else "FAIL")

E = 12, N = 10, P = 3 (2, 4, 6) > V(G) = 12 - 10 + 2 = 4 = P + 1 = 4

Viva

COCOMO Cost estimation (Exp 4)

COCOMO = COnstructive COst MOdel by Barry Boehm (1981). It estimates effort (person-months), time (months), people and cost from the size of the software in KLOC (thousand lines of code).

Effort    E = a x (KLOC)^b      person-months (PM)
Duration  D = c x (E)^d         months
People    P = E / D
Cost        = E x salary per person-month

3 types of COCOMO

COCOMO II (1995): newer version with 3 sub-models: application composition (object points), early design, post-architecture. Uses KLOC or function points.

Function points (size without code)

1. Count: EI (inputs), EO (outputs), EQ (inquiries), ILF (internal files), EIF (external files)
2. UFP = sum of count x weight   (average weights: EI 4, EO 5, EQ 4, ILF 10, EIF 7)
3. Rate 14 general system characteristics 0-5, add them = sum Fi
4. VAF = 0.65 + 0.01 x sum Fi
5. FP = UFP x VAF

LMS: EI 5, EO 3, EQ 3, ILF 3, EIF 1
UFP = 5x4 + 3x5 + 3x4 + 3x10 + 1x7 = 84
sum Fi = 38  ->  VAF = 0.65 + 0.38 = 1.03
FP = 84 x 1.03 = 86.52

In the lab: open Exp4_Cost_Estimation.xlsx (SE_Lab_Files.zip) in LibreOffice Calc, change KLOC / mode / counts, everything recalculates. Or run cost.py.

Viva

FILES Software in the lab manual and ready files

Full folder (all .dia, .gan, .xlsx, .docx, .py, git commands): SE_Lab_Files.zip (sent in chat). Office Management System full guide with every experiment: optezum.live/oms.