Description
Return Δy/Δx as slope and atan2(Δy,Δx) as directed angle in radians.
Forensic measurement calculations require a known calibration, geometric model and uncertainty convention. A converted length, ratio or residual describes the supplied measurements; it does not establish common origin, identity or evidentiary strength.
Return Δy/Δx as slope and atan2(Δy,Δx) as directed angle in radians.
When to use this tool
Use Questioned Document Baseline Slope Term when you need an explicit image or physical-measurement term.
How to use the tool and how it works
- Enter firstX, firstY, secondX, secondY. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read slope, angleRadians. Use the output convention below.
Require distinct x coordinates. Return Δy/Δx as slope and atan2(Δy,Δx) as directed angle in radians.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| firstX | First X | Required. Finite number. |
| firstY | First Y | Required. Finite number. |
| secondX | Second X | Required. Finite number. |
| secondY | Second Y | Required. Finite number. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| slope | Slope | Required. Finite number. |
| angleRadians | Angle Radians Unit: rad. | Required. Finite number. |
{
"input": {
"firstX": 0,
"firstY": 1,
"secondX": 10,
"secondY": 3
},
"output": {
"slope": 0.2,
"angleRadians": 0.19739555984988078
}
}Limitations and assumptions
- All coordinates share a scale. Directed angle can differ by π for reversed points; no handwriting identity, baseline fit, or evidentiary conclusion is inferred.
- 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 validated measurement method and original evidence for interpretation. Include calibration, geometry, uncertainty and the full evidentiary context rather than turning a numerical match into an identification.
References
Similar or alternative tools
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- Evidence Scale Perspective Length Factor
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