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.LinearVelocity;
008
009/** A unit of linear velocity like {@link edu.wpi.first.units.Units#MetersPerSecond}. */
010public final class LinearVelocityUnit extends PerUnit<DistanceUnit, TimeUnit> {
011  private static final CombinatoryUnitCache<DistanceUnit, TimeUnit, LinearVelocityUnit> cache =
012      new CombinatoryUnitCache<>(LinearVelocityUnit::new);
013
014  LinearVelocityUnit(DistanceUnit unit, TimeUnit period) {
015    super(
016        unit.isBaseUnit() && period.isBaseUnit()
017            ? null
018            : combine(unit.getBaseUnit(), period.getBaseUnit()),
019        unit,
020        period);
021  }
022
023  LinearVelocityUnit(
024      PerUnit<DistanceUnit, TimeUnit> baseUnit,
025      UnaryFunction toBaseConverter,
026      UnaryFunction fromBaseConverter,
027      String name,
028      String symbol) {
029    super(baseUnit, toBaseConverter, fromBaseConverter, name, symbol);
030  }
031
032  /**
033   * Combines a distance and time unit for form a combined unit of velocity.
034   *
035   * @param distance the unit of distance
036   * @param period the unit of time
037   * @return the combined velocity unit
038   */
039  public static LinearVelocityUnit combine(DistanceUnit distance, TimeUnit period) {
040    return cache.combine(distance, period);
041  }
042
043  @Override
044  public LinearVelocityUnit getBaseUnit() {
045    return (LinearVelocityUnit) super.getBaseUnit();
046  }
047
048  @Override
049  public LinearVelocity of(double magnitude) {
050    return new LinearVelocity(magnitude, toBaseUnits(magnitude), this);
051  }
052
053  @Override
054  public LinearVelocity ofBaseUnits(double baseUnitMagnitude) {
055    return new LinearVelocity(fromBaseUnits(baseUnitMagnitude), baseUnitMagnitude, this);
056  }
057
058  @Override
059  public LinearVelocity zero() {
060    return (LinearVelocity) super.zero();
061  }
062
063  @Override
064  public LinearVelocity one() {
065    return (LinearVelocity) super.one();
066  }
067
068  /**
069   * Combines this velocity with a time period of change to form a unit of acceleration.
070   *
071   * @param period the period of change in the velocity
072   * @return the combined acceleration unit
073   */
074  @Override
075  public LinearAccelerationUnit per(TimeUnit period) {
076    return LinearAccelerationUnit.combine(this, period);
077  }
078
079  /**
080   * Creates a ratio unit between this unit and an arbitrary other unit.
081   *
082   * @param other the other unit
083   * @param <U> the type of the other unit
084   * @return the ratio unit
085   */
086  public <U extends Unit> PerUnit<LinearVelocityUnit, U> per(U other) {
087    return PerUnit.combine(this, other);
088  }
089
090  /**
091   * Converts a measurement value in terms of another unit to this unit.
092   *
093   * @param magnitude the magnitude of the measurement in terms of the other unit
094   * @param otherUnit the other unit
095   * @return the value of the measurement in terms of this unit
096   */
097  public double convertFrom(double magnitude, LinearVelocityUnit otherUnit) {
098    return fromBaseUnits(otherUnit.toBaseUnits(magnitude));
099  }
100}