Typographed Letterpress Impression Squash Rater
Map observed letterpress impression squash to caller matched print calibration. Matched piecewise-linear calibration, no extrapolation or universal thresholds. Caller independently verifies observations, reference edition, units and applicability; not a grading-service certificate, authentication, conservation treatment, actual market price or legal/insurance entitlement.
Description
Letterpress impression or ink squash can be recorded on a measurement or reference scale.
Letterpress impression or ink squash can be recorded on a measurement or reference scale.1
This rater interpolates supplied squash observations without identifying the printing process or certifying a grade.
When to use Typographed Letterpress Impression Squash Rater
Use this tool when you need to read a measured branch response and local slope within its recorded domain. Prepare independently verified observations, reference edition/context, and matching units or currency basis.
How to use Typographed Letterpress Impression Squash Rater and understand its results
- Prepare independently verified observations, reference edition/context, and matching units or currency basis.
- Enter observedLetterpressSquashCoordinates, independentlyMatchedLetterpressSquashResponses, queryLetterpressSquashCoordinate, following the field table and calculation rules below, then run the tool.
- Read interpolatedResponse, localObservedSlope. For result objects, inspect the nested output fields below, including any missing evidence or selected indices.
- Correct any input issues and run again. Before using a successful result, review its units, signs, evidence coverage, and stated model or reference assumptions.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| observedLetterpressSquashCoordinates | Observed letterpress squash coordinates | list of number | Required |
| independentlyMatchedLetterpressSquashResponses | Independently matched letterpress squash responses | list of number | Required |
| queryLetterpressSquashCoordinate | Query letterpress squash coordinate | number | Required |
Use independently matched increasing squash coordinates and response values with an in-range query. Read the interpolated response and local slope under that supplied reference scale.
The calibration helper requires at least two nonempty aligned finite samples with coordinates strictly increasing and the query in their closed interval. Interpolate linearly between neighboring coordinates and return the segment slope. At an exact knot use its observed response and the segment to the right, except at the final knot use the last segment. Out-of-range queries fail. Tool-specific restrictions stated above still apply.
t=(query−x_i)/(x_(i+1)−x_i); response=(1−t)y_i+t y_(i+1); slope=(y_(i+1)−y_i)/(x_(i+1)−x_i) Read these symbols with the field meanings and branch or reference rules above.
| Output field | Meaning | Value type |
|---|---|---|
| interpolatedResponse | Interpolated response | number |
| localObservedSlope | Local observed slope | number |
{
"input": {
"observedLetterpressSquashCoordinates": [
1,
2,
3
],
"independentlyMatchedLetterpressSquashResponses": [
2,
4,
8
],
"queryLetterpressSquashCoordinate": 2.5
},
"output": {
"interpolatedResponse": 6,
"localObservedSlope": 4
}
}Limitations and assumptions
The branch, units, observation conditions, and response interpretation must be independently matched. Linear interpolation does not justify extrapolation, supply a universal physical or grading law, or provide uncertainty bounds.
Missing required fields, unknown fields, wrong types, and violated calculation rules return input issues. Numeric values must be finite; nonfinite numeric outputs are rejected. Arrays must be dense, with no missing cells. Numeric lists allow at most 10000 entries, subject to smaller tool-specific bounds above.
Alternative or Complementary methods
For a related task, use Recess Printing Ink Feel Ridge Test Flag: Raised ink can be an observed feature relevant to printing-method review. This checker compares supplied ink-ridge observations with explicit bands rather than identifying recess printing by touch automatically. For a complementary step, use Printing Method Identifier (recess/litho/typo) Decision Tree: Printing methods leave physical features that require independent observation and contextual interpretation. This decision aid returns caller classes compatible with supplied evidence rather than a single inferred printing method.
References
Similar or alternative tools
- Recess Printing Ink Feel Ridge Test Flag
Raised ink can be an observed feature relevant to printing-method review. This checker compares supplied ink-ridge observations with explicit bands rather than identifying recess printing by touch automatically.
- Printing Method Identifier (recess/litho/typo) Decision Tree
Printing methods leave physical features that require independent observation and contextual interpretation. This decision aid returns caller classes compatible with supplied evidence rather than a single inferred printing method.