Mindmap — Loan Calculator

Functional decomposition and test ideas for a loan calculator feature.

Nodes

  • Inputs: principal, rate, term, compounding
  • Constraints: min/max values, decimals
  • Output rounding and formatting
  • Error states and validation messages

Boundaries & Edge Cases

  • Zero/negative inputs, extremely large values
  • Rounding differences (bankers vs half-up)
  • Different compounding frequencies (daily, monthly, yearly)

Error States

  • Invalid numeric formats, locale-specific separators
  • Division-by-zero protection, overflow handling

How to Use the Mindmap

  • Drive exploratory tours per node (inputs, outputs, errors)
  • Translate nodes into checklist or pairwise models

Artifacts

  • Link to mindmap (to be added)
  • Coverage matrix (to be added)