Function Point Analysis.

I have been trying to learn the art of measuring the complexity of a software using FP analysis.

Finally i am just putting together few points which can help others too.

• Functional Point Analysis :
  
  This is a structured technique of classifying the components of the system.
  Typically used in measuring the complexity of the system.
  
  Step 1 :
  
  Divide the system in to 5 different classes.
  Transactions :
  External input (EI)
  External Output (EO)
  External Inquires (EQ)
  Logical Information
  External interface (EIF)
  Internal Logic (ILF)
  
  Step 2:
  After classifying the components into these 5 categories, we have to rank these components as High / low/ medium.
  For Transactions , use the Number or Files updated/referenced and DETs as a criteria to rank.
  For EIF and ILF use Record Element type and DET as a criteria to rank.
  
  Once you done with the ranking, we can then assign a rating for each of the measures like shown in the 3rd diagram.
  
  
  
  Step 3:
  Calculate the Unadjusted Function points:
  
  
  
  
  

  
  
  
  Step 4:
  Calculate the Value adjusted Functions point :
  
  
  This is calculated by giving a ranking for 1 to 5 for each of the following general system characteristics
  
  Data communication
  Distributed functions
  Performance objectives
  Heavily used configuration
  Transaction rate
  On-line data entry
  End-user efficiency
  On-line update
  Complex processing
  Reusability
  Installation ease
  Operational ease
  Multiple sites
  Facilitate change
  VAF = 0.65 + ( sum of 14 characteristics ) / 100
  Step 5
  The final Function Point Count is obtained by multiplying the VAF times the Unadjusted Function Point (UAF).
  FP = UAF * VAF
  Some more advantages :
  
  Can be used to track and manage scope creep.
  Can be used irrespective of technology
  Can be used to compare tool, language productive