Functional point analysis is one of the most accurate and standardized method for sizing large software projects. This guide walks you through the entire technique with a very easy to understand example

1. Skills for delivering with certainty
Introducing
Function points analysis
for dummies sizing software

2. How big is this elephant?

3. Do these guidelines help?

4. Sizing
elephant
seals

5. Welcome to Function points FP

6. A little history

7. Some geography

8. TransactionalData Function

9. Data in motion =
Transaction
Data at rest = Storage

10. How easy is this inquiry?

11.  1124 elementary processes
 All possible routes
 Cities converted to 3 char codes international nomenclature
 Reports
 Non stop
 Hop and reach
 With wide bodied air craft


12. Building blocks explained?

13. Lets learn by a case study
System : Develop the first Self driving car application ever made
Current state : Appropriate map installed shows only where the car is right
now.
To develop :
1. Show us a few possible routes between Office to Airport
2. Inputs : Start point, Destination,
3. Out put - Few possible routes ( Via Station, Bopodi, Camp etc)
4. Complexity : Thousands of possible routes between Office & Airport
5. For instance. 1000s of more or less stupid ones,
6. Only a few worth considering.
7. How to let the system choose these last ones?
8. The shortest, and the fastest one?
9. How to let the system count it?
10.How to let the car engine be controlled by map, GPS and traffic

14. Say you do complete wireframing
And.. Compute the different elements

15. Weightage points for each type

16. This is how your system points look

17. This is standard multiplication matrix

18. To get unadjusted function points
Do A *B

19. Multiply like this to get UFC
UFC = Unadjusted Function Point count

20. This is how C ( Unadjusted Function
Count UFC) looks like

21. We have not yet looked at
the
General System
Characteristics comprising
Installation ease,
Performance,
Distributedness etc

22. General System Characteristics(GSC)
or Total Degree of Influence TDI)
0 (Low) <= GSC value <= 5 (High)
Each can have
value 0 to 5

23. GSC computed
Total Degree of influence ( TDI ) = Sum of all VAFs
0 <= TDI < = 70
VAF can vary in range from 0.65 (when all GSCs are low) to 1.35 (when all GSCs are high).

24. Applying VAF( Value adjusted Function Points)
VAF = (TDI*0.01) + 0.65
For this case TDI or GSC = 44
Therefore VAF = ( 44*0.01) + 0.65
= 0.44+ 0.65
=1.09
Easy to see that
0.65< = VAF <= 1.35

25. ( For the GSM project , The Adjusted Function Points)
Adjusted FP Count = Unadjusted FP Count * VAF
In our case :
Unadjusted FP Count = C = 508
VAF = 1.09
There fore
Adjusted FP Count = 508 *1.09
= 553.72
= 554 (say)
The project is now of 554 function points

26. Organization standards needed
( Sample values)
= 0.5 person days
= 0.15 ( for <1000
fp project
= Rs 865/=

27. Organization internal projection
( Sample values)
Parame
ter
Org
standard
value/fp
Computed Project value Rounded
Value
Outside
value
Remarks
Efforts 0.5
Engineerd
ays
=554*0.5=277 280 310 Say 10 % effort
buffer
Quality 0.15 =554*0.15=83.1 90 100 10% quality
bufer
Costing 865 =554*865=4,79,210 4,80,000 7,50,000 50% Gross
margin

28. FP/Hour
Project Function Point Size
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0 50 100 150 200 250 300 350 400 450
•Every organization has an optimum size
/productivity range

29. What’s Your Message?
Happy Function
pointing
@arunpurohit