Reptile Length Landmark Offset Tool

Description

Subtract referenceCoordinate from landmarkCoordinate and multiply by positive scale for offset.

Reptile and amphibian morphometrics use landmarks, measurement paths, image scales, and supplied correction models. A numeric adjustment does not establish anatomy, growth, health, or animal welfare.

Subtract referenceCoordinate from landmarkCoordinate and multiply by positive scale for offset.

When to use this tool

Use Reptile Length Landmark Offset when you need one documented animal measurement component.

How to use the tool and how it works

Enter landmarkCoordinate, referenceCoordinate, scale. Use the units and conventions below.
Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
Read offset. Use the output convention below.

Subtract referenceCoordinate from landmarkCoordinate and multiply by positive scale for offset.^[1]

Input field	Meaning and units	Accepted input
landmarkCoordinate	Landmark Coordinate	Required. Finite number.
referenceCoordinate	Reference Coordinate	Required. Finite number.
scale	Scale	Required. Finite number; strictly above 0.

Output field	Interpretation	Returned shape
offset	Offset	Required. Finite number.

json

{
  "input": {
    "landmarkCoordinate": 120,
    "referenceCoordinate": 20,
    "scale": 0.1
  },
  "output": {
    "offset": 10
  }
}

Limitations and assumptions

Coordinates share an image or measurement axis and scale is target length per coordinate unit; no landmark identification, image calibration, or anatomical inference is performed.
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

Check measurement conventions, species-specific evidence, uncertainty, and appropriate animal-care expertise before biological or welfare decisions.

References

Calculation and input contract: herpetology/reptile-length-landmark-offset — tool.io

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