Matrix trace

matrix-trace · version 1.0.0 · Vectors & matrices · free, no key needed

Compute the trace (sum of diagonal entries) of a square finite-number matrix.

Use when you need to: matrix trace · sum of diagonal entries.

Supported

• matrix trace
• sum of diagonal entries

Not supported

• non-square matrices
• generalized trace over a sub-diagonal

Behavior

• Input matrix is a square NxN array of finite JSON numbers, N from 1 to 20, magnitude bounded to at most 1000000.
• The result is the left-to-right IEEE-754 double-precision accumulation of matrix[i][i] for every diagonal index i.
• A result of -0 is normalized to 0.

Input

• matrix (array of array of number, required): min items 1; max items 20

Output

• result (number, required)

Limits

• max dim: 20
• max abs value: 1000000

Example

Request input:

{
  "matrix": [
    [
      1,
      2
    ],
    [
      3,
      4
    ]
  ]
}

Response:

{
  "result": {
    "result": 5
  }
}

How to call it

MCP

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

{
  "id": "matrix-trace",
  "version": "1.0.0",
  "input": {
    "matrix": [
      [
        1,
        2
      ],
      [
        3,
        4
      ]
    ]
  }
}

HTTP (no key)

curl -X POST https://computefirst.net/v1/tools/matrix-trace/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"matrix":[[1,2],[3,4]]}'

The machine-readable contract is at /v1/tools/matrix-trace/versions/1.0.0.

CLI

node cli.mjs run matrix-trace 1.0.0 --input input.json --base-url https://computefirst.net

Get the client at /clients/cli/.

Related tools

• Matrix add: Add two equal-shape finite-number matrices elementwise.
• Matrix determinant: Compute the determinant of a small square finite-number matrix.
• Vector outer product: Compute the outer product of two finite-number vectors, producing a matrix.
• Matrix hadamard: Multiply two equal-shape finite-number matrices elementwise (Hadamard product).
• Matrix identity: Construct the NxN identity matrix for a given size.
• Matrix inverse: Compute the inverse of a small square finite-number matrix.