001// Copyright (c) FIRST and other WPILib contributors.
002// Open Source Software; you can modify and/or share it under the terms of
003// the WPILib BSD license file in the root directory of this project.
004
005package edu.wpi.first.units;
006
007import edu.wpi.first.units.measure.Current;
008
009/**
010 * Unit of electric current dimension.
011 *
012 * <p>This is the base type for units of current dimension. It is also used to specify the dimension
013 * for {@link Measure}: <code>Measure&lt;CurrentUnit&gt;</code>.
014 *
015 * <p>Actual units (such as {@link Units#Amps} and {@link Units#Milliamps}) can be found in the
016 * {@link Units} class.
017 */
018public final class CurrentUnit extends Unit {
019  CurrentUnit(CurrentUnit baseUnit, double baseUnitEquivalent, String name, String symbol) {
020    super(baseUnit, baseUnitEquivalent, name, symbol);
021  }
022
023  CurrentUnit(
024      CurrentUnit baseUnit,
025      UnaryFunction toBaseConverter,
026      UnaryFunction fromBaseConverter,
027      String name,
028      String symbol) {
029    super(baseUnit, toBaseConverter, fromBaseConverter, name, symbol);
030  }
031
032  @Override
033  public CurrentUnit getBaseUnit() {
034    return (CurrentUnit) super.getBaseUnit();
035  }
036
037  /**
038   * Constructs a unit of power equivalent to this unit of electrical current multiplied by another
039   * unit of voltage. For example, {@code Amps.times(Volts)} will return a unit of power equivalent
040   * to one Watt; {@code Amps.times(Millivolts)} will return a unit of power equivalent to a
041   * milliwatt, and so on.
042   *
043   * @param voltage the voltage unit to multiply by
044   * @param name the name of the resulting unit of power
045   * @param symbol the symbol used to represent the unit of power
046   * @return the power unit
047   */
048  public PowerUnit mult(VoltageUnit voltage, String name, String symbol) {
049    return Units.derive(PowerUnit.combine(voltage, this)).named(name).symbol(symbol).make();
050  }
051
052  @Override
053  public Current of(double magnitude) {
054    return new Current(magnitude, toBaseUnits(magnitude), this);
055  }
056
057  @Override
058  public Current ofBaseUnits(double baseUnitMagnitude) {
059    return new Current(fromBaseUnits(baseUnitMagnitude), baseUnitMagnitude, this);
060  }
061
062  @Override
063  public Current zero() {
064    return (Current) super.zero();
065  }
066
067  @Override
068  public Current one() {
069    return (Current) super.one();
070  }
071
072  @Override
073  public VelocityUnit<CurrentUnit> per(TimeUnit time) {
074    return VelocityUnit.combine(this, time);
075  }
076
077  /**
078   * Creates a ratio unit between this unit and an arbitrary other unit.
079   *
080   * @param other the other unit
081   * @param <U> the type of the other unit
082   * @return the ratio unit
083   */
084  public <U extends Unit> PerUnit<CurrentUnit, U> per(U other) {
085    return PerUnit.combine(this, other);
086  }
087
088  /**
089   * Converts a measurement value in terms of another current unit to this unit.
090   *
091   * @param magnitude the magnitude of the measurement in terms of the other current unit
092   * @param otherUnit the other current unit
093   * @return the value of the measurement in terms of this unit
094   */
095  public double convertFrom(double magnitude, CurrentUnit otherUnit) {
096    return fromBaseUnits(otherUnit.toBaseUnits(magnitude));
097  }
098}