Description
Calculate reference length per supplied scan length.
Orthopedic measurements distinguish side, reference origin, image scale, device lots and mechanical test geometry. A two-point load/displacement slope is structural stiffness rather than a material modulus. Supplied matches, offsets and calibration factors need verified anatomy, devices and test conditions before clinical or design interpretation.
Calculate reference length per supplied scan length.
When to use this tool
Use Model Scan Scale Factor when you already have measuredScanLength, knownReferenceLength and need to calculate reference length per supplied scan length.
How to use the tool and how it works
- Enter measuredScanLength, knownReferenceLength. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read referencePerScanFactor. Use the output convention below.
Require measuredScanLength/knownReferenceLength>0; return reference/scan as referencePerScanFactor.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| measuredScanLength | Measured Scan Length | Required. Finite number; strictly above 0. |
| knownReferenceLength | Known Reference Length | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| referencePerScanFactor | Positive reference/scan linear factor; not its inverse or an area factor. | Required. Finite number. |
{
"input": {
"measuredScanLength": 50,
"knownReferenceLength": 100
},
"output": {
"referencePerScanFactor": 2
}
}Limitations and assumptions
- This is a linear factor for matching units; it does not inspect a scan, correct distortion or establish anatomical accuracy.
- 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 actual device specifications, calibrated images and the full measurement or test setup. Use complete geometry and material/test information when relating a local scale, side match or structural secant slope to a physical or clinical question.
References
Similar or alternative tools
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