git.gag.com Git - sw/motorsim/blob - src/com/billkuker/rocketry/motorsim/RocketScience.java

   1 package com.billkuker.rocketry.motorsim;\r
   2 \r
   3 import java.text.DecimalFormat;\r
   4 import java.util.HashSet;\r
   5 import java.util.Set;\r
   6 import java.util.prefs.Preferences;\r
   7 \r
   8 import javax.measure.quantity.Pressure;\r
   9 import javax.measure.quantity.Quantity;\r
  10 import javax.measure.unit.NonSI;\r
  11 import javax.measure.unit.ProductUnit;\r
  12 import javax.measure.unit.SI;\r
  13 import javax.measure.unit.Unit;\r
  14 import javax.measure.unit.UnitFormat;\r
  15 \r
  16 import org.jscience.physics.amount.Amount;\r
  17 \r
  18 public class RocketScience {\r
  19         public static Unit<Pressure> PSI = new ProductUnit<Pressure>(NonSI.POUND_FORCE.divide(NonSI.INCH.pow(2)));\r
  20         public static Unit<Impulse> NEWTON_SECOND = new ProductUnit<Impulse>(SI.NEWTON.times(SI.SECOND));\r
  21         static{\r
  22                 UnitFormat.getInstance().label(PSI, "psi");\r
  23                 UnitFormat.getInstance().label(NEWTON_SECOND, "Ns");\r
  24         }\r
  25 \r
  26         public interface MolarWeight extends Quantity {\r
  27                 public static final Unit<MolarWeight> UNIT = new ProductUnit<MolarWeight>(\r
  28                                 SI.KILOGRAM.divide(SI.MOLE));\r
  29         }\r
  30         \r
  31         public interface Impulse extends Quantity {\r
  32                 public static Unit<Impulse> UNIT = NEWTON_SECOND;\r
  33         }\r
  34 \r
  35         public static enum UnitPreference{\r
  36                 SI(new Unit[]{\r
  37                                 javax.measure.unit.SI.MILLIMETER,\r
  38                                 javax.measure.unit.SI.MILLIMETER.divide(javax.measure.unit.SI.SECOND),\r
  39                                 javax.measure.unit.SI.NEWTON,\r
  40                                 javax.measure.unit.SI.MEGA(javax.measure.unit.SI.PASCAL),\r
  41                                 NEWTON_SECOND\r
  42                 }),\r
  43                 NONSI(new Unit[]{\r
  44                                 javax.measure.unit.NonSI.INCH,\r
  45                                 javax.measure.unit.NonSI.POUND_FORCE,\r
  46                                 javax.measure.unit.NonSI.INCH.divide(javax.measure.unit.SI.SECOND),\r
  47                                 PSI,\r
  48                                 NEWTON_SECOND\r
  49                 });\r
  50                 \r
  51                 private static UnitPreference preference = SI;\r
  52 \r
  53                 static {\r
  54                         Preferences prefs = Preferences.userNodeForPackage(RocketScience.class);\r
  55                         String p = prefs.get("PreferedUnits", "SI");\r
  56                         preference = UnitPreference.valueOf(p);\r
  57                 }\r
  58                 \r
  59                 public static UnitPreference getUnitPreference(){\r
  60                         return preference;\r
  61                 }\r
  62                 \r
  63                 public static void setUnitPreference( final UnitPreference up ){\r
  64                         preference = up;\r
  65                         Preferences prefs = Preferences.userNodeForPackage(RocketScience.class);\r
  66                         prefs.put("PreferedUnits", up.toString());\r
  67                 }\r
  68                 \r
  69                 protected Set<Unit<?>> units = new HashSet<Unit<?>>();\r
  70                 \r
  71                 UnitPreference( Unit<?> u[] ){\r
  72                         for ( Unit<?> uu : u )\r
  73                                 units.add(uu);\r
  74                 }\r
  75                 \r
  76                 @SuppressWarnings("unchecked")\r
  77                 public <T extends Quantity> Unit<T> getPreferredUnit(Unit<T> u){\r
  78                         if ( units.contains(u) )\r
  79                                 return u;\r
  80                         for( Unit<?> ret : units ){\r
  81                                 if ( ret.isCompatible(u) ){\r
  82                                         return (Unit<T>) ret;\r
  83                                 }\r
  84                         }\r
  85                         return u;\r
  86                 }\r
  87         }\r
  88 \r
  89         public static <T extends Quantity> String approx(Amount<T> a) {\r
  90                 if (a == null)\r
  91                         return "NULL";\r
  92                 Unit<T> u = RocketScience.UnitPreference.preference.getPreferredUnit(a\r
  93                                 .getUnit());\r
  94                 double d = a.doubleValue(u);\r
  95 \r
  96                 DecimalFormat df;\r
  97 \r
  98                 if (Math.abs(d) < 10.0) {\r
  99                         df = new DecimalFormat("#.##");\r
 100                 } else if (Math.abs(d) < 100.0) {\r
 101                         df = new DecimalFormat("#.#");\r
 102                 } else {\r
 103                         df = new DecimalFormat("#");\r
 104                 }\r
 105 \r
 106                 return df.format(d) + " " + u.toString();\r
 107         }\r
 108 \r
 109 }\r