Description
Express a supplied morphometric length relative to a positive reference length.
Fish records distinguish morphometric length definitions, relative image scales, annulus labels, detection times and survey-effort geometry. A supplied conversion factor need not apply across species or sizes. Local labels, ratios and nominal swept areas organize observations without identifying a fish, determining age or estimating abundance.
Express a supplied morphometric length relative to a positive reference length.
When to use this tool
Use Fish Morphometric Reference Length Ratio when you already have traitLength, referenceLength and need to express a supplied morphometric length relative to a positive reference length.
How to use the tool and how it works
- Enter traitLength, referenceLength. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read relativeLength. Use the output convention below.
Require traitLength>=0 and referenceLength>0; return trait/reference.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| traitLength | Trait Length | Required. Finite number; minimum 0. |
| referenceLength | Reference Length | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| relativeLength | Relative Length | Required. Finite number. |
{
"input": {
"traitLength": 6,
"referenceLength": 24
},
"output": {
"relativeLength": 0.25
}
}Limitations and assumptions
- Matching units and measurement definitions are assumed; no allometric model, species, age or condition is estimated.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Inspect original specimens, images, reference definitions and survey logs when verifying observations. Use a complete species-appropriate measurement or population method for age, abundance or condition questions; local scales and effort terms preserve only their stated basis.
References
Similar or alternative tools
- Fish Standardlength Bodydepth Ratio
Calculate supplied fish standard length relative to body depth.
- Fish Length Frequency Bin
Check a fish-length record against a supplied bin with optional upper inclusion.