Android Open Source - AstroPhysCalc Unit Util

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License

The source code is released under:

Apache License

Java Source Code

package org.astrophyscalc;
/*w  w w.j  a  v a2 s  .  c  om*/
import java.util.HashSet;
import java.util.Set;


public class UnitUtil {

  final static String EMPTY_UNIT_SET = "Units cannot be an empty set";
  final static String MULTIPLE_UNITS = "UnitExpression contains multiple items.";
  final static String UNITTED_VALUE_NULL = "ValueAndUnits cannot be null.";
  final static String UNIT_EXPR_NOT_SINGLE_UNIT_DIM_ONE = "UnitExpression must contain single unit of dimension one.";

  public static Set<UnitExpression> getTimeExpressionsExclude(final TimeUnit ... excludes) {
    final Set<TimeUnit> excludedSet = new HashSet<TimeUnit>();
    for (TimeUnit u: excludes) {
      excludedSet.add(u);
    }

    final Set<UnitExpression> exprs = new HashSet<UnitExpression>();
    for (TimeUnit u : TimeUnit.values()) {
      if (!excludedSet.contains(u)) {
        exprs.add(UnitExpression.createFromUnit(u));
      }
    }
    return exprs;
  }

  public static Set<UnitExpression> getTimeExpressions(final TimeUnit ... units) {
    final Set<TimeUnit> unitSet = new HashSet<TimeUnit>();
    for (TimeUnit u: units) {
      unitSet.add(u);
    }

    final Set<UnitExpression> exprs = new HashSet<UnitExpression>();
    for (TimeUnit u : unitSet) {
      exprs.add(UnitExpression.createFromUnit(u));
    }
    return exprs;
  }

  public static Set<UnitExpression> getLengthExpressions(final LengthUnit ... units) {
    final Set<LengthUnit> unitSet = new HashSet<LengthUnit>();
    for (LengthUnit u: units) {
      unitSet.add(u);
    }

    final Set<UnitExpression> exprs = new HashSet<UnitExpression>();
    for (LengthUnit u : unitSet) {
      exprs.add(UnitExpression.createFromUnit(u));
    }
    return exprs;
  }


/*
  public static Unit getBestUnit(final ValueAndUnits vu, final Set<Unit> units) {
    if (vu == null) {
      throw new IllegalArgumentException(UNITTED_VALUE_NULL);
    }
    if(vu.getUnitExpression() == UnitExpression.DIMENSIONLESS) {
      return null;
    }
    if (!vu.getUnitExpression().isSingleUnitDimOne()) {
      throw new IllegalArgumentException(UNIT_EXPR_NOT_SINGLE_UNIT_DIM_ONE);
    }

    final double value = vu.getValue();
    if (value == 0) {
      return units.iterator().next().getBase();
    }
    double bestRatio = 1;
    Unit bestUnit = null;
    for (Unit unit : units) {
      double absValInUnits = Math.abs(value / unit.inBaseUnits());
      double ratio = absValInUnits > 1 ? absValInUnits: 1 / absValInUnits;
      if (absValInUnits == 1) {
        return unit;
      }
      if (bestUnit == null) {
        bestUnit = unit;
        bestRatio = ratio;
      }
      else {
        if (ratio < bestRatio) {
          bestUnit = unit;
          bestRatio = ratio;
        }
      }
    }
    return bestUnit;
  }
*/
/*  public ValueAndUnits getInBestUnits(final UnitSelector selector) {
    return selector.
  }

  public static class UnitSelector {

    private final Set<UnitSelectionRule> rules;

    public UnitSelector create(final Set<UnitSelectionRule> rules) {
      return new UnitSelector(rules);
    }

    private UnitSelector(final Set<UnitSelectionRule> rules) {
      this.rules = rules;
    }

    public ValueAndUnits getInBestUnits() {

    }

  }

  public static class UnitSelectionRule {

    private final ValueAndUnits vu;
    private final UnitExpression expr;

    public UnitSelectionRule create(final ValueAndUnits vu, final UnitExpression expr) {
      return new UnitSelectionRule(vu, expr);
    }

    private UnitSelectionRule(final ValueAndUnits vu, final UnitExpression expr) {
      this.vu = vu;
      this.expr = expr;
    }

    public ValueAndUnits getValueAndUnits() {
      return vu;
    }

    public UnitExpression getUnitExpression() {
      return expr;
    }
  }
*/
}

Java Source Code List

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