Description
Return distance = hypot(secondStation-firstStation,secondOffset-firstOffset).
A range or engineering coordinate needs a declared geometric and measurement convention. A local orthogonal station-offset distance and a quantization half-width are limited models, rather than general geographic distance or measurement accuracy.
Return distance = hypot(secondStation-firstStation,secondOffset-firstOffset).
When to use this tool
Use Road Chainage Offset Distance Pair when checking the stated local geometry or rounding-resolution envelope.
How to use the tool and how it works
- Enter firstStation, secondStation, firstOffset, secondOffset. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read distance. Use the output convention below.
Return distance = hypot(secondStation-firstStation,secondOffset-firstOffset).1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| firstStation | First Station | Required. Finite number. |
| secondStation | Second Station | Required. Finite number. |
| firstOffset | First Offset | Required. Finite number. |
| secondOffset | Second Offset | Required. Finite number. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| distance | Euclidean norm in an assumed common straight-road orthogonal station-offset frame. | Required. Finite number. |
{
"input": {
"firstStation": 10,
"secondStation": 13,
"firstOffset": 2,
"secondOffset": 6
},
"output": {
"distance": 5
}
}Limitations and assumptions
- Station and offset must use the same length unit and a common locally orthogonal straight-road frame. Curved chainage coordinates are not globally Cartesian, so this is not general geographic or road-network distance.
- 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 actual road geometry or a complete calibrated measurement-uncertainty budget when the simplified assumption is insufficient.
References
Similar or alternative tools
- Wing Landmark Scale Gap
pixelDistance is their Euclidean separation; inferredLength = pixelDistance/suppliedPixelsPerLength; lengthGap = inferredLength-referenceLength.
- Signed Ray Distance Behind Origin Flag
Project a point onto a ray’s supporting line and flag a parameter behind the origin.