Systems Testing and Quality Assurance Techniques

Checklist: Numeric Entry

The following edits, questions, and checks should be considered for all
numeric fields.

Edit / Question Example
Maximum Value & Minimum Value
  • Edit Picture (z, 9, #, etc.)
  • Field Width
  • Boundaries (Upper Limit, Lower Limit)
  • Positive and Negative Numbers
  • Precision (Whole Numbers and Decimal Places)
  • Signed or Unsigned
Delta – Smallest increment used by system
  • Whole Numbers
  • Fractions
  • Decimal Value
Other Tests
  • Overflow
  • Underflow
  • Rounding
  • Floating Point Errors
Formats
  • Currency (Symbol, Separators, Commas & Period)
  • Input
  • Storage
  • Output
  • Display
  • Print
  • Integer (16, 32, 64)
  • Floating Point
  • Binary
  • Packed
  • Hex, Octal, Scientific Notation
  • Placement of Negative Indicator
  • -, CB, ( ) Leading or Trailing
  • Word Boundaries
Attributes
  • Position (Display or Print)
  • Color (Red for Negative)
  • Intensity
  • Blinking
  • Font Size
  • Italics
Zero
  • Leading 0123
  • Trailing 123.0
  • Absent 123.
Spaces Before or After Entry
  • Permitted?
  • Self Correcting?
Alternative Formats
  • Display values in thousands or millions
  • Display as words "One Thousand"
  • Roman numerals
Error Message
  • When displayed
  • Where displayed
  • Should they be acknowledged?
  • Automatic Recovery?
Initialization
  • Starting Value
  • Null Value
  • Reset Value
Reasonableness Checks  
Entry Format
  • Character
  • Numeric
Match other formats
  • Usage in a calculator
  • Appended to another field
Display Issues
  • Blank on either side of field to prevent touching another field
  • 123 123 vs. 123123
  • Display with leading zero
Will conversion take place?  
Source of Value
  • Will it change?
  • Multiple?
  • Alternative Source
Can value be computed?  
Balancing instructions Audit Issues
Encrypted storage  
Is a check digit required? Check digit computation
Validation
  • Table
  • Computation
  • Other report
Does field have other use?
  • SSN, SIN, Employee ID
  • Salary, Speed
  • Date
  • Lookup Key
Naming Conventions  
Compiler Requirements  

Note the edits that are performed by the programming language, tests that
should be handled during unit testing, and checks that should be done via
integration or system testing.

Other issues:

  1. Will boundaries and limits change over time?
  2. Are they influenced by something else?
  3. Will field accept operators? +, -, /, *, !, **, ^, %
  4. Will the value change format?
    64 bit to 16 bit
    Character to numeric
    Display to packed
    Display to scientific notation
    Display to words
  5. Will value move across platforms?
  6. Why is the field being treated as numeric?
  7. Will voice recognition be necessary?
This post was written by Sanford M. Sorkin, Professor, Temple University