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

java

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

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

Fluent Builder

java

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

Range Queries

java

// 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

java

ElectronicPart capacitor = ...;

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

Utility Methods

java

// 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

java

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

Find Precision Resistors

java

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

Filter BOM by Manufacturer

java

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

Find Capacitors in Value Range

java

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

Integration with BOM

java

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:

java

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

3. Null Handling

java

// 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:

java

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.

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