Description
Return 2×asin(intake/(2×radius)).
Angle-based pattern calculations distinguish linear intake, chord, arc and unoriented grain direction. Degrees and radians are not interchangeable, and a local geometric relationship does not model fabric deformation or three-dimensional fit.
Return 2×asin(intake/(2×radius)).
When to use this tool
Use Dart Intake Rotation Angle Term when you need a stated pattern-angle or arc relationship.
How to use the tool and how it works
- Enter intake, radius. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read angleRadians. Use the output convention below.
Require positive radius and intake between zero and twice radius. Return 2×asin(intake/(2×radius)).1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| intake | Chord length across the circular model, not arc length. | Required. Finite number; minimum 0. |
| radius | Radius in the common length unit, with its geometric role defined above. | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| angleRadians | Angle Radians | Required. Finite number. |
{
"input": {
"intake": 2,
"radius": 2
},
"output": {
"angleRadians": 1.0471975511965979
}
}Limitations and assumptions
- Intake is modeled as a chord, not arc length, and output is radians. Actual dart construction, ease and fit are not verified.
- 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 full pattern geometry and a suitable construction sample when rotation, grain behavior or fit matters. Verify angle units, branch choice and the meaning of intake before applying an identity.
References
Similar or alternative tools
- Dart Rotation Seam Length Gap
Return each radius×angle arc and (secondRadius-firstRadius)×angle gap.
- Collar Roll Line Offset Term Tool
Model parallel circular roll lines at a caller-supplied radius and sweep.