Description
Return next knot minus current knot and zero for an exact repeated pair.
Interpolation knots divide a coordinate range into intervals. Repeated nodes, unequal spacing, and exact boundary selection can change how a piecewise interpolant is interpreted.
Return next knot minus current knot and zero for an exact repeated pair.
When to use this tool
Use Spline Knot Interval Zero Span Flag when you need one knot-interval or multiplicity diagnostic.
How to use the tool and how it works
- Enter knots, index. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read span, zero. Inspect zero before interpreting the associated values.
Require nondecreasing knots and a valid adjacent interval index. Return next knot minus current knot and zero for an exact repeated pair.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| knots | Knots | Required. Array of finite number; maximum items 256. |
| index | Zero-based position or diagnostic index under the calculation above; inspect any sentinel policy. | Required. Safe integer; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| span | Coordinate interval width; its unit must match the derivative convention. | Required. Finite number. |
| zero | Zero | Required. Boolean. |
{
"input": {
"knots": [
0,
0,
1
],
"index": 0
},
"output": {
"span": 0,
"zero": true
}
}Limitations and assumptions
- Repeated knots are allowed intentionally; this does not decide spline continuity or construct a spline.
- 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
Validate the complete knot sequence and interpolation method, including tolerance and extrapolation policies.
References
Similar or alternative tools
- Interpolation: Interpolation Knot Multiplicity Count
Require nondecreasing knots and count entries exactly equal to target.
- Knot Coalescence Distance
Compute abs(secondKnot - firstKnot).