Overview
After specifying the source and target units using from() and to(), you can execute the conversion using one of three methods:
convert() - Returns a decimal number (most common)convertToFraction() - Returns a fraction object with numerator and denominatorconvertToRational() - Returns a Rational object (for internal use)
All three methods perform the same conversion but return the result in different formats.
import { LengthUnitConverter } from 'univerto/length';
import { LENGTH_UNIT } from 'univerto/length';
const conversion = LengthUnitConverter
.from(100, LENGTH_UNIT.CENTIMETER)
.to(LENGTH_UNIT.METER);
conversion.convert(); // 1
conversion.convertToFraction(); // { numerator: 1, denominator: 1 }
conversion.convertToRational(); // Rational { numerator: 1, denominator: 1 }
convert()
Returns the conversion result as a decimal number.
Signature:
The converted value as a decimal number
When to Use
Use convert() when you need:
- A simple numeric result for calculations
- Display values in your UI
- Integration with existing numeric operations
This is the most commonly used conversion method.
Examples
Basic Conversion
import { MassUnitConverter } from 'univerto/mass';
import { MASS_UNIT } from 'univerto/mass';
const kilograms = MassUnitConverter
.from(1000, MASS_UNIT.GRAM)
.to(MASS_UNIT.KILOGRAM)
.convert();
console.log(kilograms); // 1
Using Result in Calculations
import { LengthUnitConverter } from 'univerto/length';
import { LENGTH_UNIT } from 'univerto/length';
const meters = LengthUnitConverter
.from(5, LENGTH_UNIT.KILOMETER)
.to(LENGTH_UNIT.METER)
.convert();
const area = meters * meters; // 25000000
Chaining Conversions
import { TimeUnitConverter } from 'univerto/time';
import { TIME_UNIT } from 'univerto/time';
const hours = TimeUnitConverter
.from(120, TIME_UNIT.MINUTE)
.to(TIME_UNIT.HOUR)
.convert();
const days = TimeUnitConverter
.from(hours, TIME_UNIT.HOUR)
.to(TIME_UNIT.DAY)
.convert();
console.log(days); // 0.08333...
convertToFraction()
Returns the conversion result as a fraction with separate numerator and denominator.
Signature:
convertToFraction(): { numerator: number; denominator: number }
An object containing the fraction representationThe numerator of the fraction
The denominator of the fraction
When to Use
Use convertToFraction() when you need:
- High-precision arithmetic without floating-point errors
- To preserve exact ratios
- To display results as fractions in UI
- To perform further rational arithmetic
Examples
Basic Fraction Conversion
import { LengthUnitConverter } from 'univerto/length';
import { LENGTH_UNIT } from 'univerto/length';
const fraction = LengthUnitConverter
.from(1, LENGTH_UNIT.INCH)
.to(LENGTH_UNIT.CENTIMETER)
.convertToFraction();
console.log(fraction);
// { numerator: 127, denominator: 50 }
// Exact: 2.54 cm
High-Precision Arithmetic
import { MassUnitConverter } from 'univerto/mass';
import { MASS_UNIT } from 'univerto/mass';
const fraction = MassUnitConverter
.from(1, MASS_UNIT.POUND)
.to(MASS_UNIT.GRAM)
.convertToFraction();
// Use fraction for precise calculations
const { numerator, denominator } = fraction;
const totalGrams = (numerator * 10) / denominator;
Displaying Fractions
import { VolumeUnitConverter } from 'univerto/volume';
import { VOLUME_UNIT } from 'univerto/volume';
const fraction = VolumeUnitConverter
.from(0.5, VOLUME_UNIT.GALLON)
.to(VOLUME_UNIT.LITER)
.convertToFraction();
const display = `${fraction.numerator}/${fraction.denominator} liters`;
console.log(display);
Converting Back to Decimal
const fraction = LengthUnitConverter
.from(100, LENGTH_UNIT.CENTIMETER)
.to(LENGTH_UNIT.METER)
.convertToFraction();
const decimal = fraction.numerator / fraction.denominator;
console.log(decimal); // 1
convertToRational()
Returns the conversion result as a Rational object. This method is primarily for internal use.
Signature:
convertToRational(): Rational
A Rational object containing the conversion result
When to Use
Use convertToRational() when you need:
- To perform further rational arithmetic operations
- Internal library operations
- Custom precision handling
Note: For most use cases, prefer convert() or convertToFraction() instead.
Rational Class Methods
The Rational object provides the following methods:
toNumber() - Convert to decimal numbertoFraction() - Convert to fraction objectmultiply(other: Rational) - Multiply by another Rationaldivide(other: Rational) - Divide by another Rational
Examples
Basic Usage
import { LengthUnitConverter } from 'univerto/length';
import { LENGTH_UNIT } from 'univerto/length';
const rational = LengthUnitConverter
.from(100, LENGTH_UNIT.CENTIMETER)
.to(LENGTH_UNIT.METER)
.convertToRational();
console.log(rational.toNumber()); // 1
console.log(rational.toFraction()); // { numerator: 1, denominator: 1 }
Rational Arithmetic
import { Rational } from 'univerto/core';
const rational1 = LengthUnitConverter
.from(100, LENGTH_UNIT.CENTIMETER)
.to(LENGTH_UNIT.METER)
.convertToRational();
const rational2 = Rational.fromNumber(2);
const result = rational1.multiply(rational2);
console.log(result.toNumber()); // 2
Implementation Details
All three methods use the same underlying conversion algorithm:
- Convert the source value to a Rational number
- Calculate the conversion factor from source to target unit
- Multiply the rational value by the conversion factor
- Format the result according to the method:
convertToRational() - Returns the Rational object directlyconvertToFraction() - Calls toFraction() on the Rationalconvert() - Calls toNumber() on the Rational
// Internal implementation
function convertToRational() {
const from = scale[fromUnit];
const to = scale[targetUnit];
const fromRational = Rational.fromNumber(fromQuantity);
const factor = from.divide(to);
return fromRational.multiply(factor);
}
function convertToFraction() {
const fromRational = convertToRational();
return fromRational.toFraction();
}
function convert() {
const result = convertToRational();
return result.toNumber();
}
See Also
