Lemonergy · Studio block

Extract diagonal

Extracts a main or offset matrix diagonal.

Implementation ID: native-extract-diagonal
Reviewed: 2026-10-27

Behavior

yᵢ = Aᵢ,ᵢ₊offset, using valid diagonal indices. The worked example connects this operation to signals in Lemonergy Studio.

Interface

Original Lemonergy interface view. Lines identify ports; they are not a completed simulation circuit.

Ports and observed outputs
Name	Direction	Unit	Meaning
`in0`	input	1	Matrix; real 2 × 2 array.
`out0`	output	1	Diagonal; real 2 array.

Parameters

Defaults are initial model values. Select values for your own model and operating conditions.

Configuration fields
Parameter	Unit	Default	Meaning and limits
Diagonal offset `params[0]`	1	0	0 main diagonal; positive above; negative below.

Equations and rules

yᵢ = Aᵢ,ᵢ₊offset, using valid diagonal indices

Worked example

Extract diagonal — worked example

Matrix = [1,3,2,4]. Diagonal at 0 s = [1,4].

Open Studio example after release →

Numerical checks for the bundled synthetic example
Output	Time (s)	Expected value	Unit	Absolute tolerance
Diagonal `out0`	0	`[1, 4]`	1	1e-08

Explore the recorded outputs

Extract diagonal recorded example

Extract diagonal [1]

Extract diagonal [1]: 1 — at 0 s

2 actual recorded samples. Lines are visual guides between samples. Synthetic example, not measured cell data.

Download the recorded samples (JSON) · Open this Studio example after release

Use in a workflow

Extract diagonal — worked example

Extracts a main or offset matrix diagonal.

Extract diagonal: yᵢ = Aᵢ,ᵢ₊offset, using valid diagonal indices. The worked example connects this operation to signals in Lemonergy Studio.
- Use the block reference for settings and connections.
- Implementation tested locally; public release pending.

Open Studio example after release

Connected concepts

Limits and interpretation

Shapes and element types are explicit. Values must be finite; automatic reshaping and unit conversion are not performed.

Scientific and mathematical references

These sources explain the scientific and mathematical background. The behavior, interface and limits above define the Lemonergy implementation; a citation does not imply every model option in the source is implemented.

NIST Digital Library of Mathematical Functions, §3.2 Linear Algebra
National Institute of Standards and Technology
Technical reference · Linear algebra and matrix operations; conceptual background, not software certification.

Implementation sources

This reference follows the public interface and locally verified numerical checks for an upcoming release.

Contract: Lemonergy Studio public contract · Verification record: verification-2026-10-27

docs/glossary/native-block-verification.json

This implementation and its workflow uses (JSON) · Knowledge graph (JSON-LD)