Lemonergy · Studio block
FIR filter
Applies a finite set of weighted current and previous input samples.
- Implementation ID
native-fir-filter- Reviewed
- 2026-10-27
Behavior
y[k] = Σᵢ bᵢ u[k−i]. The worked example connects this operation to signals in Lemonergy Studio.
Interface
| Name | Direction | Unit | Meaning |
|---|---|---|---|
in0 | input | 1 | Value; real scalar. |
out0 | output | 1 | Filtered; real scalar. |
Parameters
Defaults are initial model values. Select values for your own model and operating conditions.
| Parameter | Unit | Default | Meaning and limits |
|---|---|---|---|
Sample periodsampleTimeS | s | 0.1 | Exact sample grid period. Elapsed-time integration begins after initialization. Minimum 1e-06 |
Tap coefficientstables[0] | 1 | [0.25, 0.5, 0.25] | Current sample coefficient first. |
Denominatortables[1] | 1 | [1] | FIR denominator is [1]. |
Equations and rules
y[k] = Σᵢ bᵢ u[k−i]
Worked example
| Output | Time (s) | Expected value | Unit | Absolute tolerance |
|---|---|---|---|---|
Filteredout0 | 0 | 1 | 1 | 1e-08 |
Explore the recorded outputs
FIR filter recorded example
FIR filter11 actual recorded samples. Lines are visual guides between samples. Synthetic example, not measured cell data.
Read the selected signal as a table
| Time (s) | Value |
|---|
Download the recorded samples (JSON) · Open this Studio example after release
Use in a workflow
FIR filter — worked example
Applies a finite set of weighted current and previous input samples.
- FIR filter: y[k] = Σᵢ bᵢ u[k−i]. 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.
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.
- Introduction to Digital Filters with Audio Applications — Difference Equation
Julius O. Smith III · Author text, Stanford CCRMA; online edition hosted by DSPRelated · 2007
Technical reference · Causal FIR/IIR difference equations and coefficient/history conventions.
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)