W 5 HH Principle W 5 HH Principle

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W 5 HH Principle

W 5 HH Principle

W 5 HH Principle • W 5 means 5 ‘wh’ Questions. • & •

W 5 HH Principle • W 5 means 5 ‘wh’ Questions. • & • ‘HH’ means two ‘How’ questions

5 ‘wh’ Questions 1. Why the system is being developed? Need of the system

5 ‘wh’ Questions 1. Why the system is being developed? Need of the system Role of the software in the business Ex. Amazon website, BSNL website 2. What will be done? Task set required for the project. Process models, architectural models etc. 3. When it will be done? Project schedule In between milestones

4. Who is responsible for the function? Role & responsibility Of each member of

4. Who is responsible for the function? Role & responsibility Of each member of the software team Is identified & described. 5. Where they are organizationally located? Location of – customers, users and other stakeholders

two ‘How’ questions 1. How will the job be done, technically and managerially? Management

two ‘How’ questions 1. How will the job be done, technically and managerially? Management strategy & Technical strategy For the project, is decided. 2. How much of each resource is needed? estimates are developed For the required resources – like – cost, duration and manpower

Metrics in the process and project domains

Metrics in the process and project domains

Process Metrics • Metrics ? • Measurements – • Processes are measured • Using

Process Metrics • Metrics ? • Measurements – • Processes are measured • Using different parameters/arttributes. • • • Like – size of the process Resources required to execute the process Time required to execute the process Dependency on another processes

 • Quality of the software • is based on • These metrics

• Quality of the software • is based on • These metrics

Project Metrics • Project metrics are 1. Estimation of cost and duration (schedule) 2.

Project Metrics • Project metrics are 1. Estimation of cost and duration (schedule) 2. Error detection Intent of project metrics 1. To avoid delays 2. To minimize risks

Software Measurement

Software Measurement

 • Direct measures – Size & function oriented metrics - cost & effort

• Direct measures – Size & function oriented metrics - cost & effort applied LOC produced Execution speed & defects • Indirect measures Functionality Quality Complexity Efficiency Reliability Maintainability etc.

Size oriented metrics • LOC

Size oriented metrics • LOC

Example Of LOC Based Estimation • Consider an ABC project, with some important modules

Example Of LOC Based Estimation • Consider an ABC project, with some important modules – such as – 1. user interface & control facilities 2. 2 D graphics analysis 3. 3 D graphics analysis 4. Database management 5. Computer graphics display facility 6. Peripheral control function 7. Design analysis models • Estimate the project – based on LOC

 • Consider each module as separate function • The corresponding LOC can be

• Consider each module as separate function • The corresponding LOC can be estimated in the following table Function Estimated LOC User interface & control facilities 2500 2 D graphics analysis 5600 3 D graphics analysis 6450 Database management 3100 Computer graphics display facility 4740 Peripheral control function 2250 Design analysis models 7980 Total estimation in LOC 32620

A review of historical data indicates – 1. Average productivity is = 500 LOC/month/person

A review of historical data indicates – 1. Average productivity is = 500 LOC/month/person 2. Average labor cost is = Rs. 6000/month Then cost for LOC can be estimated as – Cost/LOC = (6000/500) = Rs 12/LOC By considering, total estimated LOC as = 32620 Total estimated project cost = (32620 * 12) = Rs. 3, 91, 440/- Total estimated project effort = (32620 / 500) = 65 Person-months = 2 months 5 days (will be required for 1 Person) If we use 5 persons, then 13 days will require. If we use 10 persons, then 6. 5 days will require. If we use 15 persons, then 4. 3 days will require.

Size Oriented Metrics • Size of the software – to be produced – is

Size Oriented Metrics • Size of the software – to be produced – is considered. • It is a direct measure of – software.

Table - Size Measure Project LOC Effort Cost($) Document (Pages) Errors Defects People ABC

Table - Size Measure Project LOC Effort Cost($) Document (Pages) Errors Defects People ABC 10000 20 170 400 12 4 PQR 20000 60 300 800 150 32 10 XYZ 30000 65 522 1200 50 20 . . .

 • A simple set of – size measure – that can be developed

• A simple set of – size measure – that can be developed is – • • • Size = kilo lines of code (KLOC) Productivity = KLOC / person – month Quality = number of faults / KLOC Cost = Rs / KLOC Documentation = Pages of documentation / KLOC

 • Size of the software – Can be measured as – - Lines

• Size of the software – Can be measured as – - Lines of code - 1000 LOC = 1 KLOC • 1 LOC = one line of text, In a source file. • While counting LOC – - Don’t count blank lines Don’t count comments Count everything else

 • Size Estimation • Lines of Code (LOC) • If LOC is simply

• Size Estimation • Lines of Code (LOC) • If LOC is simply a count of the number of lines • then figure shown below contains 18 LOC. • When comments and blank lines are ignored, • the program in figure shown below contains 17 LOC. Fig. : Function for sorting an array 1. int. sort (int x[ ], int n) 2. { 3. int i, j, save, im 1; 4. /*This function sorts array x in ascending order */ 5. If (n<2) return 1; 6. for (i=2; i<=n; i++) 7. { 8. im 1=i-1; 9. for (j=1; j<=im; j++) 10. if (x[i] < x[j]) 11. { 12. Save = x[i]; 13. x[i] = x[j]; 14. x[j] = save; 15. } 16. } 17. return 0; 18. }

 • Expected LOC for 3 d Geometric Analysis function – three point estimation

• Expected LOC for 3 d Geometric Analysis function – three point estimation is – • Optimistic estimation - 4700 • most likely estimation - 6000 • Pessimistic estimation – 10000 • S = [Sopt + (4 * Sm) + Spess ] / 6

 • Expected value [4700 + (4 * 6000) + 10000] / 6 =

• Expected value [4700 + (4 * 6000) + 10000] / 6 = 6450 A review of historical data indicates – 1. Average productivity is = 500 LOC/month 2. Average labor cost is = Rs. 6000/month Then cost for LOC can be estimated as – Cost/LOC = (6000/500) = Rs 12/LOC By considering, total estimated LOC as = 32620 Total estimated project cost = (32620 * 12) = Rs. 3, 91, 440/- Total estimated project effort = (32620 / 500) = 65 Person-months = 2 months 5 days (for 1 Person)