Download Article: SNAP_APM_2_2

Part 1 – The SNAP Method
Categories & Sub-categories
2.3 Multiple Input Methods
Definition
The ability of the application to provide its functionality while accepting
multiple input methods.
SCU
The elementary process.
Terms
Input Method
A technique or media type, which is used to deliver data into the assessed
application, such as bar code reader, fax, PDF, office document, screen,
voice message, SMS, smart mobile device etc.
The assessed application may need to identify the input method in order to
interpret and use the received information.
Complexity
Parameters:
1. The number of data element types (DET’s) in the SCU.
SNAP Points
calculation
Identify the complexity based on the number of DET’s. Calculate size based
on the constant factor and the number input methods.
Note:
When counting a new development project, the number of input methods
should include the additional ones only, assuming that one of the input
methods is the base method.
2. The number of additional input methods.
For example, if the new development uses 4 input methods, the number of
additional input methods is 3.
Input Methods Complexity
SP=
Low
Average
High
1-4 DET’s
5-15 DET’s
16+ DET’s
3*# additional
input methods
4*# additional
input methods
6*# additional
input methods
Table 1-16 SNAP sizing for Multiple Input Methods
Rules
May 2015
This category should be used to when there are multiple types of inputs used
to invoke the same functionality. If the different input types differ in terms of
DETs, FTRs and processing logic, then they would already have been
accounted as separate functions in function point counting process.
If they are same, then multiple input methods should be used.
Check the following
1) Approach taken for FP counting - single instance or multiple instance
2) The multiple methods of input for the same functionality (Same DETs,
FTRS and processing logic) have not been included for FP size
calculation. In other words, if the FP count has been done using single
instance approach for different media types, then the additional input
Assessment Practices Manual
5-27