Sparse Coordinate Triplet Transpose

Description

Transpose COO coordinate records and swap matrix dimensions without sorting, combining duplicates or dropping explicit zeros.

A sparse matrix can be stored as coordinate triplets or as pointer/index/value arrays. Stored entries are not necessarily distinct numerical nonzeros: duplicates and explicit zeros can matter to representation checks. Row and column coordinates here are zero-based, and omitted entries are handled only as stated for the particular operation.

Transpose COO coordinate records and swap matrix dimensions without sorting, combining duplicates or dropping explicit zeros.

When to use this tool

Use this tool to transpose COO coordinate records and swap matrix dimensions without sorting, combining duplicates or dropping explicit zeros.

How to use the tool and how it works

Enter tripletsJson, rows, columns using the field definitions below. For JSON text, serialize the explicit records in the shown shape.
Run the operation. Correct input errors before interpreting an output.
Read result.rows, result.columns, result.triplets. Use the ordering, boundary rules and absence conditions described below.

Swap every triplet’s row and column and swap the declared dimensions, preserving values and record order.^[1]

Input field	Meaning and units	Accepted input
tripletsJson	JSON array of records with zero-based row, column and finite value fields.	Text, at most 8,192 UTF-16 code units; the operation’s grammar also applies.
rows	Declared row count; coordinate operations use 0–128, dense budgets allow larger integers.	A finite safe integer within the operation’s stated bounds.
columns	Declared column count; coordinate operations use 0–128, dense budgets allow larger integers.	A finite safe integer within the operation’s stated bounds.

These are the decoded structures used in the example’s JSON text fields. Supply the corresponding serialized JSON strings as input.

json

{
  "tripletsJson": [
    {
      "row": 0,
      "column": 1,
      "value": 2
    },
    {
      "row": 0,
      "column": 1,
      "value": 3
    },
    {
      "row": 1,
      "column": 0,
      "value": 0
    }
  ]
}

Output field	Interpretation
result	Object containing the named fields below.
result.rows	Resulting row count.
result.columns	Resulting column count.
result.triplets	Stored {row, column, value} records under the operation’s stated ordering and duplicate policy.

json

{
  "input": {
    "tripletsJson": "[{\"row\":0,\"column\":1,\"value\":2},{\"row\":0,\"column\":1,\"value\":3},{\"row\":1,\"column\":0,\"value\":0}]",
    "rows": 2,
    "columns": 2
  },
  "output": {
    "result": {
      "rows": 2,
      "columns": 2,
      "triplets": [
        {
          "row": 1,
          "column": 0,
          "value": 2
        },
        {
          "row": 1,
          "column": 0,
          "value": 3
        },
        {
          "row": 0,
          "column": 1,
          "value": 0
        }
      ]
    }
  }
}

Limitations and assumptions

Transpose does not combine duplicates, prune zeros or sort coordinates.
Triplets are JSON records with row, column and value. Coordinate shapes are ordinarily bounded to 128 per axis; compressed major dimensions are limited to 127 for pointer-list capacity. The dense-budget operation has separate larger shape limits and returns exact counts as decimal text.
Every declared top-level input field is required and unexpected fields are rejected. Ordinary strings are limited to 8,192 UTF-16 code units and lists to 128 entries, with tighter operation-specific bounds where stated. JSON text has bounded nesting and node counts.
Numeric outputs must be finite and no larger in absolute magnitude than the safe-integer limit; operations returning exact large integers use decimal text. Positions are zero-based and spans end exclusively unless the operation explicitly states a different convention.

Alternative or Complementary methods

Distinguish stored-record counts, coordinate-pattern checks and arithmetic matrix properties. Combine duplicates or prune zeros explicitly when required, and use a matrix library for numerical linear algebra.

References

Tool behavior and example: Sparse Coordinate Triplet Transpose — tool.io

Similar or alternative tools

Sparse Coordinate Axis Offset
Translate bounded COO coordinates into explicitly supplied target dimensions; out-of-target entries are rejected rather than clipped.
Sparse Coordinate Column Counts
Count COO entry occurrences per column, including duplicate coordinates and explicit zero values; not dense nonzero support.