Proportional vs Tabular Numeral Width Check
Audit caller measured numeral advances for exact or tolerance-based tabularity; observation coverage must be known and equality does not prove activated font feature.
Description
Tabular figures use equal advances, while proportional figures may differ.
Tabular figures use equal advances, while proportional figures may differ. A calibration sample should remain distinct from full-digit coverage.1
Enter exactly three calibration advances or all ten digits, each positive, and nonnegative tolerance. Return spread, inclusive gate and exact equality flag.
When to use Proportional vs Tabular Numeral Width Check
Use Proportional vs Tabular Numeral Width Check when you need to evaluate the supplied records under the calculation and evidence rules below. No font feature is activated or digit coverage independently verified.
Prepare measured font or typeset-layout values and the explicit design policy requested. For text or font bytes, use the supported syntax explained below.
How to use Proportional vs Tabular Numeral Width Check and understand its results
- Prepare measured font or typeset-layout values and the explicit design policy requested. For text or font bytes, use the supported syntax explained below.
- Enter observedNumeralAdvances, callerEqualWidthTolerance using the field table and calculation rules, then run the tool.
- Read observedAdvanceSpread, withinCallerTabularTolerance, exactlyEqualAdvances. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| observedNumeralAdvances | Observed numeral advances | list of number | Required |
| callerEqualWidthTolerance | Caller equal width tolerance | number | Required |
Enter exactly three calibration advances or all ten digits, each positive, and nonnegative tolerance. Return spread, inclusive gate and exact equality flag.
spread=max(advances)−min(advances); pass=spread≤tolerance Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| observedAdvanceSpread | Observed advance spread | number |
| withinCallerTabularTolerance | Within caller tabular tolerance | boolean |
| exactlyEqualAdvances | Exactly equal advances | boolean |
{
"input": {
"observedNumeralAdvances": [
500,
500,
501
],
"callerEqualWidthTolerance": 1
},
"output": {
"observedAdvanceSpread": 1,
"withinCallerTabularTolerance": true,
"exactlyEqualAdvances": false
}
}Limitations and assumptions
No font feature is activated or digit coverage independently verified.
Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Numeric lists are limited to 10,000 entries; string lists to 128 strings of at most 128 characters each. The rules above may impose smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors. A successfully returned false flag is an evaluated outcome; its meaning is explained above.
Alternative or Complementary methods
Use Figure Space Monospace Equal Width Check: Figure-space width can be checked against each measured numeral advance. A monospace name alone does not establish equality. For a complementary task, use Oldstyle Figure Alignment Checker: Oldstyle-figure evidence can include descenders and varied tops. Observed geometry alone cannot verify an activated font feature.
References
Similar or alternative tools
- Figure Space Monospace Equal Width Check
Figure-space width can be checked against each measured numeral advance. A monospace name alone does not establish equality.
- Oldstyle Figure Alignment Checker
Oldstyle-figure evidence can include descenders and varied tops. Observed geometry alone cannot verify an activated font feature.