Examples
Examples
Try the starting example
- Species abundance counts
- 10,5,3,2
- Logarithm base
- 2.718281828459045
- Shannon diversity
- 1.207974
- Pielou evenness
- 0.871369
- Observed species count
- 4
Try another scenario
- Species abundance counts
- [5, 5, 5, 5]
- Logarithm base
- 2.718281828459045
- Shannon diversity
- 1.386294
- Pielou evenness
- 1
- Observed species count
- 4
Calculation method
Calculation method
Shannon diversity
−sum(p log_base p), zero abundance terms omitted.
Pielou evenness
Shannon/log_base(number of observed species); one species has evenness0.
Observed species count
Number of positive abundance entries.
Symbols and units
- a
- Species abundance counts
- b
- Logarithm base
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Calculation steps and notation
sum(list) adds all entries in the list.
Assumptions & limits
Assumptions & limits
- Species abundance counts, log base. Returns Diversity and evenness. All coefficients and observations are user supplied; results describe only the stated mathematical model. Quantities are deterministic calculations from supplied observations and assumptions; no external data is fetched. Supported limits: Finite inputs only; numeric fields bounded as labelled. Lists and JSON records are limited to 256 entries unless a stricter tool bound is stated. No automatic design approval, legal conclusion, treatment recommendation or safety certification. Species abundance counts: minimum 0, maximum 1000000000000.0. Logarithm base: minimum 1e-12, maximum 1000000000000.0.
Are these inputs private?
These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.
Further reading
Background reading; this does not imply endorsement or independent review of SumFizz.