Description
Calculate supplied canvas-length fractional and percentage changes.
Conservation records distinguish measured areas, source-qualified condition labels, storage clearances and light exposure. Lux-hours measure photometric exposure, whereas material response depends on spectrum and sensitivity. A nominal inverse-square distance ratio or geometric mask share does not establish an appropriate treatment or safe display limit.
Calculate supplied canvas-length fractional and percentage changes.
When to use this tool
Use Canvas Relative Stretch Measurement when you already have referenceLength, observedLength and need to calculate supplied canvas-length fractional and percentage changes.
How to use the tool and how it works
- Enter referenceLength, observedLength. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read relativeChange, changePercent. Use the output convention below.
Require referenceLength>0 and observedLength>=0; return (observed-reference)/reference and 100 times that change.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| referenceLength | Reference Length | Required. Finite number; strictly above 0. |
| observedLength | Observed Length | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| relativeChange | Relative Change | Required. Finite number. |
| changePercent | Change Percent | Required. Finite number. |
{
"input": {
"referenceLength": 100,
"observedLength": 101
},
"output": {
"relativeChange": 0.01,
"changePercent": 1
}
}Limitations and assumptions
- Sign is expansion-positive. Units and axis must match; no tension, material strain field, stability or suitable treatment is inferred.
- 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
Use calibrated observations and the complete conservation, lighting or transport assessment. Check material response, geometry, history and actual condition before applying local ratios, exposure terms or labels to an object.
References
Similar or alternative tools
- Paper Relative Thickness Change
Calculate a supplied relative paper-thickness change.
- Drawing Grid Scale Factor
Calculate supplied drawing-grid linear and area scale factors.