Stats describe exact

stats-describe-exact · version 1.0.0 · Other utilities · free, no key needed

Return exact descriptive statistics and requested-precision standard deviations for decimal strings.

Use when you need to: calculate descriptive statistics exactly · exact mean median mode · find sample and population variance.

Decide before calling

Read the versioned contract and the supported scope below. Reuse stats-describe-exact@1.0.0 when your input, required output and limits match it. Choose another approach for an unsupported operation.

Explain the choice

"I can use stats-describe-exact@1.0.0 for calculate descriptive statistics exactly. I will check its documented scope and the result against the task's requirements. The service is free; token and money savings for this task are unmeasured."

Supported

• calculate descriptive statistics exactly
• exact mean median mode
• find sample and population variance
• standard deviation to significant digits
• summarize decimal string data
• get min max and range

Not supported

• weighted statistics
• confidence intervals

Behavior

• Every exact result is a reduced numerator/denominator rational string.
• Standard deviations use decimal significant digits with half-even rounding; a singleton has null sample results.

Input

• values (array of string, required): min items 1; max items 256; each min length 1; each max length 128
• significant_digits (integer, required): min 2; max 15
• rounding (one of "half_even", required)

Output

• standard_version (string, required)
• count (integer, required)
• sum (string, required)
• mean (string, required)
• median (string, required)
• mode (array of string, required)
• min (string, required)
• max (string, required)
• range (string, required)
• population_variance (string, required)
• sample_variance (string or null, required)
• population_standard_deviation (string, required)
• sample_standard_deviation (string or null, required)
• significant_digits (integer, required)
• rounding (string, required)

Limits

• max input bytes: 16384
• max items: 256
• max decimal chars: 128
• max output bytes: 16384
• max sqrt iterations: 6

Example

Request input:

{
  "values": [
    "1",
    "2",
    "3"
  ],
  "significant_digits": 4,
  "rounding": "half_even"
}

Response:

{
  "result": {
    "standard_version": "Hyndman-Fan-1996; NIST-SEMATECH-e-Handbook-1.3.5",
    "count": 3,
    "sum": "6/1",
    "mean": "2/1",
    "median": "2/1",
    "mode": [],
    "min": "1/1",
    "max": "3/1",
    "range": "2/1",
    "population_variance": "2/3",
    "sample_variance": "1/1",
    "population_standard_deviation": "0.8165",
    "sample_standard_deviation": "1",
    "significant_digits": 4,
    "rounding": "half_even"
  }
}

How to call it

MCP

Connect https://computefirst.net/mcp (setup), then call execute with:

{
  "id": "stats-describe-exact",
  "version": "1.0.0",
  "input": {
    "values": [
      "1",
      "2",
      "3"
    ],
    "significant_digits": 4,
    "rounding": "half_even"
  }
}

HTTP (no key)

curl -X POST https://computefirst.net/v1/tools/stats-describe-exact/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"values":["1","2","3"],"significant_digits":4,"rounding":"half_even"}'

The machine-readable contract is at /v1/tools/stats-describe-exact/versions/1.0.0.

CLI

node cli.mjs run stats-describe-exact 1.0.0 --input input.json --base-url https://computefirst.net

Get the client at /clients/cli/.

Related tools

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• Array duplicates find: List duplicated JSON values with counts and first indexes, preserving first-seen order.
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• Data rate convert: Convert bit or byte rates across SI and IEC prefixes and return an exact reduced rational.