Counter Wrap Increment Decoder

Decode modular sampled counter increments under explicit at-most-one-wrap/no-reset assumptions; hidden multiple wraps are not recoverable.

Description

Decode modular sampled counter increments under explicit at-most-one-wrap/no-reset assumptions; hidden multiple wraps are not recoverable.

A bounded counter may wrap to zero while its accumulated quantity continues increasing. Modular differences recover the smallest compatible increment between readings.

When to use this tool

Decode modular sampled counter increments under explicit at-most-one-wrap/no-reset assumptions; hidden multiple wraps are not recoverable.

Prepare the supplied counts, modulus fields for this operation.
Compare the complete example with the representation used by your own input before carrying the result into another step.

How to use the tool and how it works

Enter counts, modulus. Use the exact text syntax, units and index conventions explained below.
Run the tool. If input validation fails, correct the supplied fields before interpreting any result.
Read result.increments, result.assumption. Interpret false, null and empty lists using the distinctions below; they can be valid outputs.

Require integer readings from zero through modulus minus one. For each adjacent pair, normalize their difference into that same modular range and return the increments with the stated one-wrap/no-reset assumption.^[1]

Input field	Meaning and representation	Accepted input
counts	counts.	List of finite numbers; bounded by the operation
modulus	modulus.	Integer from 1 to 1e12 inclusive

Output field	Interpretation
result	Object containing the named outputs below.
result.increments	The increments list in the ordering and representation described above.
result.assumption	The assumption value under the stated formula or text convention.

json

{
  "input": {
    "counts": [
      8,
      1,
      3
    ],
    "modulus": 10
  },
  "output": {
    "result": {
      "increments": [
        3,
        2
      ],
      "assumption": "at-most-one-wrap-and-no-reset-between-samples"
    }
  }
}

Limitations and assumptions

Multiple wraps and resets cannot be distinguished from readings alone. Equal readings produce zero even if a full modulus of activity occurred; this is not an independently verified total.
Every declared top-level field is required and unexpected fields are rejected. Numeric inputs must be finite; ordinary text fields are bounded to 8,192 UTF-16 code units, with tighter operation-specific limits where stated.
Ordinary string lists have at most 128 entries of at most 128 code units each; numeric lists and matrices have separate bounded size checks. Nonfinite results and excessively large serialized outputs are rejected.
Indexes are zero-based and spans have an exclusive end unless explicitly stated otherwise. A valid false, null or empty-list result is distinct from malformed input.

Alternative or Complementary methods

Choose a sampling model before combining results. Earlier-sample hold, linear interpolation and index-only differences answer different questions; event cooldown, debounce and rolling limits also use different acceptance rules.

References

Tool behavior and example: Counter Wrap Increment Decoder — tool.io

Similar or alternative tools

Counter Reset Segmenter
Segment a nonnegative sampled counter at decreases interpreted as reset candidates; resets and wraps cannot be distinguished from values alone.
Consecutive Threshold Streaks
Tabulate sampled consecutive threshold streaks with explicit at-or-above versus strictly-below convention; no between-sample duration inference.