Description
Selection delay from a zero-based scan target and explicit completed cycles.
Activity and assistive-task records distinguish planned, attempted, completed, assisted, observed, and optional components. Shares depend on the selected denominator and credit policy. A supplied code, geometry, or time-budget calculation is separate from evaluating an individual's function or safe access.
Selection delay from a zero-based scan target and explicit completed cycles.
When to use this tool
Use Assistive Switch Scan Selection Time when you need this specific task-count, assistance-code, timing, equipment-budget, or participation-record component.
How to use the tool and how it works
- Enter positions, targetIndex, cyclesBefore, dwellSeconds, activationSeconds. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read scanSteps, expectedSeconds. Use the output convention below.
For positive integer positions, valid zero-based targetIndex, nonnegative integer cyclesBefore, and nonnegative dwellSeconds and activationSeconds return scanSteps=cyclesBefore*positions+targetIndex and expectedSeconds=scanSteps*dwellSeconds+activationSeconds.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| positions | Positions | Required. Safe integer; minimum 1. |
| targetIndex | Target Index | Required. Safe integer; minimum 0. |
| cyclesBefore | Cycles Before | Required. Safe integer; minimum 0. |
| dwellSeconds | Dwell Seconds | Required. Finite number; minimum 0. |
| activationSeconds | Activation Seconds | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| scanSteps | Scan Steps | Required. Safe integer. |
| expectedSeconds | Deterministic supplied scan-time model, not a fitted user-specific expectation. | Required. Finite number. |
{
"input": {
"positions": 8,
"targetIndex": 3,
"cyclesBefore": 1,
"dwellSeconds": 0.5,
"activationSeconds": 0.2
},
"output": {
"scanSteps": 11,
"expectedSeconds": 5.7
}
}Limitations and assumptions
- Expected means the supplied deterministic timing model, not a statistical expectation fitted to a user. No missed selections, switch activation variability, fatigue, or safe/appropriate assistive configuration is assessed.
- 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 the intended assessment and a complete task or access model when a local check is insufficient. Verify task definitions, credit policies, measurement units, and the context of the underlying observations.
References
Similar or alternative tools
- Assistive Switch Scan Wrap Token
Advance a supplied zero-based scanning index with exact signed wrap count.
- Assistive Device Clearance Residual
Supplied nominal bench clearance only, without assistive-device fit or safety advice.