HomeCalculatorsMathLinear AlgebraRow Space Calculator
Math calculator

Row Space Calculator

Row space of a small real square matrix from nonzero RREF rows. Same engine as Linear System. Trivial rowspace is {0}. Left-nullspace is a sibling. Runs locally.

Instant result
Result
—

Enter values to calculate.

Inputs—
Mode—
Formula—
Trust summary CVP VERIFIED · production STALE · CVP protocol 1.0.0-proposed · Core assurance · all published modes
Input interpretation
Enter values to calculate.
Result
—
Verified scope
all published modes
Assurance
Core
Declared partition coverage
PASS · 19/19 declared partitions (solve, det, inverse, multiply, transpose, rank, eigen, lu, chol, qr, svd, lstsq, rref, condition, nullspace, columnspace, rowspace, leftnullspace, invalid-domain) · Matrix
Known limitations
  • Core CVP does not include live graph, viewport, or pointer interaction.
Model
A basis for row A of a small real square matrix (order 2–4), with dim = rank A.
Scope
Real square matrices
Verification
Engine tested · Specification checked · v1.14.1 · CVP VERIFIED · production STALE · CVP protocol 1.0.0-proposed · Core assurance · all published modes· View Manifest · CVP overview · Specification
Versions
Calculation 1.14.1 · CVP protocol 1.0.0-proposed · Evidence 2026-10-07.solve-publication-diagnostics
Verification revision
2026-10-07.solve-publication-diagnostics · 10/10 property · digest c6132667b855
Legacy regression
58/58 tests · Production surface contract 5/5
Trust layers
Verification VERIFIED · Production STALE · Overall CVP state: VERIFIED_STALE under CVP 1.0.0-proposed
CVP status
STALE · Capability production binding: STALE · Site report: STALE · Evidence changed after the last successful production attestation. Re-attestation required.
Reference
O1 model · O2 expected_values · O2 numerical_behavior
Interfaces
PASS · UI (SSR) / REST / MCP — ui-ssr is query-result HTML, not a live browser session. Error-path engine·REST·MCP 1/1 (status, code, calculation_version). SSR compared on URL-canonical requested calculations; empty query is idle (not an error) and JSON-typed object/array inputs are REST/MCP-only.
Supplemental domain review
Not performed
Named expert review
Not performed
CVP suite
26/26 golden · 8/8 CVP boundary · 14/14 invalid · 10/10 property · 1/1 metamorphic · 9/9 cross-interface · 2/2 cross-calculator · 5/5 CVP contract · Manifest
Specification basis
  • ISO 80000-2:2019 Quantities and units — Mathematics
Specification basis
Evidence
29 legacy golden · 6 legacy boundary · legacy regression suite · 26/26 oracle-backed golden · 14/14 invalid · Artifact integrity PASS
STALE · Build schema 1.14.1 matches page · production binding STALE · Semantic contract ✓ · Last attestation PASS · current evidence changed · re-attestation required · CVP STALE · attestation STALE — Production CURRENT withheld · Public/cache ✓ · Origin ✓
Semantic contract
PASS
Full verification

Manifest identity, reference classes, interfaces, suite, and production records.

Formulas

Core equations used by this calculator.

Dimensiondim row A = rank A
Transposerow A = im Aᵀ
iSquare matrices only, order ≤ 4. Reuses Gauss–Jordan already used by inverse, rank, RREF, nullspace, and column space. Not a CAS. Left-nullspace is /calc/math/left-nullspace. Float64. Pivot tests are scale-aware (ε·max(m,n)·‖A‖_max).

How to use

1

Enter a square matrix

2×2 or 3×3. Larger composition lives at /workspace/matrix. Rank, RREF, nullspace, and column space are sibling discovery URLs.

2

Read the basis

A zero matrix returns {0}. Otherwise each nonzero RREF row is a basis vector, with residual of the least-squares fit of every original row onto that basis.

Example calculations

Common configurations with formula and result.

ϟ

Rank 1

[[1,2],[2,4]]

dim = 1
[1, 2]
ϟ

Identity

I₂

rank = n
[[1,0],[0,1]]

Row Space calculator specification

Version 1.14.0 · Engine tested

Calculation status

Review policy · Evidence

Definition
row A is the span of the rows of A. This page is mode=rowspace on math.linear_algebra. A basis is the nonzero rows of RREF. Not a second engine. Left-nullspace is /calc/math/left-nullspace.
What it calculates
A basis for row A of a small real square matrix (order 2–4), with dim = rank A.
Inputs
  • order
  • a11…
Outputs
  • basis
  • dimension
  • rank
  • trivial
  • residual_max
Formula
dim row A = rank A
Assumptions
  • Real square matrices
  • Order ≤ 4
  • Planar ℝ² figure when order=2; order 3+ omits it
  • Float64
  • Not a CAS
  • Not Jordan form as a product
Units
  • dimensionless
Boundary conditions
  • zero matrix → trivial rowspace {0}
  • unknown mode (including jordan-form) → INVALID_MODE
Example
[[1,2],[2,4]] → basis [[1,2]], dim=1
Validation cases

2 published on this page · 58/58 tests · Production surface contract 5/5 · View evidence

  • order=2 a11=1 a12=2 a21=2 a22=4 → dimension=1, basis=[[1,2]]
  • mode=jordan-form order=2 a11=1 a12=0 a21=0 a22=1 → INVALID_MODE
Specification basis
  • ISO 80000-2:2019 Quantities and units — Mathematics
Calculation version
1.14.0

Other calculators in this family: Cholesky Factorization Calculator, Column Space Calculator, Condition Number Calculator, Least Squares Calculator, Left Nullspace Calculator, Linear System Calculator, LU Factorization Calculator, Matrix Determinant Calculator . Explore all Linear Algebra.

→ Cholesky Factorization Calculator Lower Cholesky factorization of a small real symmetric positive-definite matrix. Same engine as Linear System. Not LU. Not a CAS. Runs locally. › → Column Space Calculator Column space (image) of a small real square matrix from RREF pivot columns. Same engine as Linear System. Trivial image is {0}. Left-nullspace is a sibling. Runs locally. › → Condition Number Calculator κ₁(A) = ‖A‖₁ ‖A⁻¹‖₁ for a small real square matrix. Same engine as Linear System. Singular matrices return infinite. Not a 2-norm product. Runs locally. › → Least Squares Calculator Linear least squares for a small real matrix, square or rectangular. Full column rank uses QR; otherwise SVD. Same engine as Linear System. Not Statistics regression. Runs locally. › → Left Nullspace Calculator Left-nullspace (cokernel) of a small real square matrix as ker(Aᵀ). Same engine as Linear System. Trivial left kernel is {0}. Not Jordan form. Runs locally. › → Linear System Calculator Solve small linear systems Ax = b, plus det, inverse, rank, LU, Cholesky, QR, SVD, least squares, RREF, condition number, nullspace, column space, rowspace, left-nullspace, and eigenvalues. Same engine as the matrix workspace. Not a CAS. Runs locally. › → LU Factorization Calculator Doolittle LU factorization with partial pivoting for a small real matrix. Same engine as Linear System. Not a CAS. Runs locally. › → Matrix Determinant Calculator Determinant of a small real matrix. Same engine as Linear System and the matrix workspace. Not a CAS. Runs locally. ›

Frequently asked questions

Key distinctions behind the calculation.

Is this a second linear-algebra engine?

No. It is mode=rowspace on math.linear_algebra, the same engine as /calc/math/linear-system and /workspace/matrix. It reuses the RREF already used by /matrix-rref.

Does this return the left-nullspace?

No. This seed is the row space. Left-nullspace is /calc/math/left-nullspace on this same engine.