Lib-electronic-components parametric-search

Parametric Search Skill

install

source · Clone the upstream repo

git clone https://github.com/Cantara/lib-electronic-components

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/Cantara/lib-electronic-components "$T" && mkdir -p ~/.claude/skills && cp -r "$T/.claude/skills/parametric-search" ~/.claude/skills/cantara-lib-electronic-components-parametric-search && rm -rf "$T"

manifest: .claude/skills/parametric-search/SKILL.md

source content

Parametric Search Skill

This skill provides guidance for using the ParametricSearch utility to filter electronic components by their specifications.

Overview

ParametricSearch

enables filtering collections of

ElectronicPart

objects using unit-aware parametric queries. It supports:

Comparison operators (>=, <=, >, <, =, !=)
Range queries (min..max)
Set membership (IN)
Automatic unit parsing (nF, uF, kΩ, etc.)

Quick Reference

Query Syntax

Syntax	Example	Matches
`>= value`	`>= 10nF`	Capacitors 10nF and above
`<= value`	`<= 50V`	Voltage 50V and below
`> value`	`> 1k`	Resistance above 1kΩ
`< value`	`< 1uF`	Capacitance below 1µF
`= value`	`= X7R`	Exact string match
`!= value`	`!= X5R`	Not equal to string
`min..max`	`10nF..1uF`	Range (inclusive)
`IN(a,b,c)`	`IN(X7R, X5R)`	Any of listed values

Unit Prefixes

Prefix	Multiplier	Example
p	10⁻¹²	100pF
n	10⁻⁹	100nF
u/µ	10⁻⁶	10uF, 10µF
m	10⁻³	100mV
k/K	10³	10k, 10K
M	10⁶	1M
G	10⁹	1GHz

Usage Patterns

Static Filter Method

Map<String, String> requirements = Map.of(
    "capacitance", ">= 10nF",
    "voltage", ">= 25V",
    "dielectric", "IN(X7R, X5R)"
);

List<ElectronicPart> results = ParametricSearch.filter(capacitors, requirements);

Fluent Builder

List<ElectronicPart> results = ParametricSearch.search(capacitors)
    .min("capacitance", "10nF")
    .max("voltage", "50V")
    .in("dielectric", "X7R", "X5R", "C0G")
    .find();

Range Queries

// Find resistors between 1kΩ and 100kΩ
List<ElectronicPart> results = ParametricSearch.search(resistors)
    .range("resistance", "1k", "100k")
    .find();

// Equivalent using where()
List<ElectronicPart> results = ParametricSearch.search(resistors)
    .where("resistance", "1k..100k")
    .find();

Single Part Check

ElectronicPart capacitor = ...;

if (ParametricSearch.meets(capacitor, "capacitance", ">= 10nF")) {
    // Part meets requirement
}

Utility Methods

// Count matching parts
long count = ParametricSearch.search(parts)
    .min("voltage", "25V")
    .count();

// Check if any match
boolean hasHighVoltage = ParametricSearch.search(parts)
    .min("voltage", "100V")
    .anyMatch();

// Get first match
Optional<ElectronicPart> first = ParametricSearch.search(parts)
    .equals("dielectric", "C0G")
    .findFirst();

Builder Methods

Method	Description
`where(key, requirement)`	Add any requirement string
`min(key, value)`	Add `>= value` requirement
`max(key, value)`	Add `<= value` requirement
`range(key, min, max)`	Add `min..max` requirement
`equals(key, value)`	Add `= value` requirement
`notEquals(key, value)`	Add `!= value` requirement
`in(key, values...)`	Add `IN(values)` requirement
`find()`	Execute and return List
`findFirst()`	Execute and return Optional
`count()`	Execute and return count
`anyMatch()`	Execute and return boolean

Searchable Fields

From specs Map

Any key in

ElectronicPart.getSpecs()

```
capacitance
```
,
```
resistance
```
,
```
inductance
```
```
voltage
```
,
```
current
```
,
```
power
```
```
tolerance
```
,
```
tempco
```
```
dielectric
```
,
```
material
```
Custom spec keys

Built-in Fields

Key	Field
`value`	`getValue()`
`package` , `pkg`	`getPkg()`
`manufacturer` , `mfr`	`getManufacturer()`
`description` , `desc`	`getDescription()`
`mpn`	`getMpn()`

Common Use Cases

Find High-Voltage X7R Capacitors

List<ElectronicPart> results = ParametricSearch.search(capacitors)
    .min("voltage", "50V")
    .equals("dielectric", "X7R")
    .find();

Find Precision Resistors

List<ElectronicPart> results = ParametricSearch.search(resistors)
    .where("tolerance", "<= 0.1%")
    .in("package", "0402", "0603", "0805")
    .find();

Filter BOM by Manufacturer

List<ElectronicPart> murataOnly = ParametricSearch.search(bomEntries)
    .equals("manufacturer", "Murata")
    .find();

Find Capacitors in Value Range

List<ElectronicPart> decouplingCaps = ParametricSearch.search(capacitors)
    .range("capacitance", "100nF", "10uF")
    .min("voltage", "16V")
    .in("dielectric", "X7R", "X5R")
    .find();

Integration with BOM

public List<BOMEntry> findObsoleteHighValueParts(BOM bom) {
    return ParametricSearch.search(bom.getBomEntries())
        .min("capacitance", "10uF")  // High value
        .find()
        .stream()
        .filter(ElectronicPart::isLifecycleAtRisk)  // Obsolete
        .map(p -> (BOMEntry) p)
        .toList();
}

Gotchas

1. Case Sensitivity

Unit prefixes:
```
m
```
= milli,
```
M
```
= mega (case matters!)
k/K: Both work for kilo
String values: Case-insensitive (
```
X7R
```
matches
```
x7r
```
)

2. Missing Specs

Parts without the requested spec are excluded from results:

// Part without "voltage" spec will NOT be in results
ParametricSearch.filter(parts, Map.of("voltage", ">= 25V"));

3. Null Handling

// Empty/null collection returns empty list
ParametricSearch.filter(null, requirements);  // []
ParametricSearch.filter(List.of(), requirements);  // []

// Null/empty requirements returns all parts
ParametricSearch.filter(parts, null);  // all parts
ParametricSearch.filter(parts, Map.of());  // all parts

4. Unit Stripping

Units are stripped for comparison:

```
"50V"
```
and
```
"50"
```
compare as equal
```
"10kΩ"
```
and
```
"10k"
```
compare as equal

5. Works with Subclasses

BOMEntry

extends

ElectronicPart

, so filtering works:

List<BOMEntry> entries = ...;
List<ElectronicPart> results = ParametricSearch.filter(entries, requirements);
// Results can be cast back to BOMEntry if needed

Performance Notes

Predicates are built once per filter() call
Each part is evaluated against all predicates
For large collections, consider pre-filtering by type first
No indexing - O(n) per filter operation

Learnings & Quirks

January 2026

BigDecimal comparison: Use
```
compareTo()
```
, not
```
equals()
```
-
```
1E+3
```
equals
```
1000
```
by value
Micro symbol: Both
```
u
```
and
```
µ
```
are supported for micro prefix
Percentage handling:
```
1%
```
parses to
```
1
```
, not
```
0.01
```
(matches how tolerances are typically specified)
Existing typed spec infrastructure: The library has
```
SpecValue
```
,
```
SpecUnit
```
,
```
BaseComponentSpecs.meetsRequirements()
```
, and
```
ComponentValueStandardizer
```
- a comprehensive typed spec system.
```
ParametricSearch
```
bridges the gap between
```
ElectronicPart.specs
```
(Map<String, String>) and these typed systems.
Two spec systems exist:
```
ElectronicPart.specs
```
uses strings, while
```
ComponentSpecification
```
uses typed
```
SpecValue<?>
```
. ParametricSearch works with the string-based system which is more commonly used.

Lib-electronic-components parametric-search

Parametric Search Skill

Overview

Quick Reference

Query Syntax

Unit Prefixes

Usage Patterns

Static Filter Method

Fluent Builder

Range Queries

Single Part Check

Utility Methods

Builder Methods

Searchable Fields

From specs Map

Built-in Fields

Common Use Cases

Find High-Voltage X7R Capacitors

Find Precision Resistors

Filter BOM by Manufacturer

Find Capacitors in Value Range

Integration with BOM

Gotchas

1. Case Sensitivity

2. Missing Specs

3. Null Handling

4. Unit Stripping

5. Works with Subclasses

Performance Notes

Related Classes

Learnings & Quirks

January 2026