Description
Subtract a supplied forensic blank-sample quantity from an observation.
Forensic records distinguish exhibit identity, container links, declared conclusions, timestamp resolution and measurement bases. A matching seal string or recorded certificate is not authentication or proof of custody. Redacted display text and salt-version labels also do not by themselves establish sufficient de-identification or lawful disclosure.
Subtract a supplied forensic blank-sample quantity from an observation.
When to use this tool
Use Forensic Blank Sample Subtraction when checking the stated exhibit record, measurement, time or display-policy convention.
How to use the tool and how it works
- Enter sampleSignal, blankSignal. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read correctedSignal. Use the output convention below.
Return sampleSignal-blankSignal as signed correctedSignal in one common measurement unit.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| sampleSignal | Sample Signal | Required. Finite number. |
| blankSignal | Blank Signal | Required. Finite number. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| correctedSignal | Corrected Signal | Required. Finite number. |
{
"input": {
"sampleSignal": 12.5,
"blankSignal": 2
},
"output": {
"correctedSignal": 10.5
}
}Limitations and assumptions
- Negative corrections are retained; no detection threshold, blank suitability, uncertainty or evidential identification 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
Review verified original evidence and custody records using qualified forensic and legal assessment for actual interpretation, disclosure and evidential decisions.
References
Similar or alternative tools
- Forensic Sample Dry Wet Mass Ratio
Express supplied forensic sample masses on a dry/wet ratio basis.
- Exhibit Sub Sample Volume Balance
Calculate a signed exhibit-volume balance after withdrawals and returns.