/* * * * * * * * * *     CONVERT SCRIPT    * * * * * * * * * *\
*                                                             *
*    Converts between U.S./Imperial and SI (Metric) units.    *
*                                                             *
*        --  Written by Bo Johansson  1998-11-10  --          *
*        --      Area measures added  1999-02-21  --          *
*        --  Pressure measures added  2000-05-17  --          *
*        --        Opera 4 bug fixes  2000-10-14  --          *
*                                                             *
*   --   http://w1.545.telia.com/~u54504162/index_e.htm   --  *
\* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

function VOL_MEASURES()
{
  this.mCubic_meter = 1000
//  this.mHectoliter = 100
//  this.mDekaliter = 10
  this.mLiter = 1
  this.mDeciliter = 0.1
  this.mCentiliter = 0.01
  this.mMilliliter = 0.001
  this.mCubic_millimeter = 0.000001
  
//  this.mcTable_spoon=0.015
//  this.mcTea_spoon=0.005

  this.uscCubic_inch = 0.016387064
  this.uscAcre_foot = 43560 * 1728 * this.uscCubic_inch
  this.uscCubic_yard = 27 * 1728 * this.uscCubic_inch
  this.uscCubic_foot = 1728 * this.uscCubic_inch
  
  this.uslGallon = 231 * this.uscCubic_inch
  this.uslBarrel = 42 * this.uslGallon
  this.uslQuart =  this.uslGallon / 4
  this.uslPint =  this.uslGallon / 8
  this.uslGill =  this.uslGallon / 32
  this.uslFluid_ounce = this.uslGallon / 128
  this.uslFluid_dram =  this.uslGallon / 1024
  this.uslMinim = this.uslFluid_ounce / 61440
  
  this.usdBarrel = 7056 * this.uscCubic_inch
  this.usdBushel = 2150.42 * this.uscCubic_inch
  this.usdPeck = this.usdBushel / 4
  this.usdQuart = this.usdBushel / 32
  this.usdPint = this.usdBushel / 64
  
//  this.uscCup = 8 * this.uslFluid_ounce
//  this.uscTable_spoon = this.uslFluid_ounce / 2
//  this.uscTea_spoon = this.uslFluid_ounce / 6
  
//  this.briGallon = 4.54609
//  this.briBarrel = 36 * this.briGallon
//  this.briBushel = 8  * this.briGallon
//  this.briPint = this.briGallon / 8
//  this.briFluid_ounce = this.briGallon / 160
}


function WEIGHT_MEASURES()
{
  this.mTon = 1000
  this.mKilogram = 1
  this.mGram = 0.001
  this.mMilligram = 0.000001

  this.avdpPound = 0.45359237
//  this.briTon = 2240 * this.avdpPound
  this.usTon = 2000 * this.avdpPound
//  this.briCWT = 112 * this.avdpPound
  this.usCWT = 100 * this.avdpPound
//  this.briStone = 14 * this.avdpPound     // *** Added 2000-05-17
  this.avdpOunce = this.avdpPound / 16
//  this.avdpDram= this.avdpPound / 256
//  this.avdpGrain = this.avdpPound / 7000

//  this.troyPound = 5760 * this.avdpGrain
//  this.troyOunce = 480 * this.avdpGrain
//  this.troyDWT = 24 * this.avdpGrain
//  this.troyGrain = this.avdpGrain
}


function LENGTH_MEASURES()
{
  this.mKilometer = 1000
  this.mMeter = 1
  this.mDecimeter = 0.1
  this.mCentimeter = 0.01
  this.mMillimeter = 0.001

  this.engFoot = 0.3048
  this.engMile = 5280 * this.engFoot
  this.engFurlong = 660 * this.engFoot
  this.engYard = 3 * this.engFoot
  this.engInch = this.engFoot / 12
  this.engMil = this.engFoot / 12000
  
  this.nautMile = 1852
  this.nautFathom = 6 * this.engFoot
}


function AREA_MEASURES()              //******* function added 1999-02-21
{
  this.mSquare_kilometer = (1000 * 1000)
//  this.mHectare = (100 * 100)
//  this.mAre = 100
  this.mSquare_meter = 1
  this.mSquare_decimeter = (0.1 * 0.1)
  this.mSquare_centimeter = (0.01 * 0.01)
  this.mSquare_millimeter = (0.001 * 0.001)

  this.engSquare_foot = (0.3048 * 0.3048)
  this.engSquare_yard = (3 * 3 * this.engSquare_foot)
  this.usSquare_rod = (16.5 *16.5 * this.engSquare_foot)
  this.engAcre = 160 * this.usSquare_rod
  this.engSquare_mile = (5280 *5280 * this.engSquare_foot)
  this.engSquare_inch = (this.engSquare_foot / (12 * 12))
}


function PRESS_MEASURES()              //******* function added 2000-05-17
{
  this.mKilopascal = 1000
  this.mHectopascal = 100
  this.mPascal = 1
  this.mBar = 100000
  this.mMillibar = 100
  this.mAtm = 101325
  this.mMillimeter_Hg = this.mAtm / 760

  this.engInch_Hg = 25.4 * this.mMillimeter_Hg
  
  this.engPound_sq_inch = 6894.757 
  this.engPound_sq_foot = this.engPound_sq_inch / 144
}


var vol_data = new VOL_MEASURES();

var weight_data = new WEIGHT_MEASURES();

var length_data = new LENGTH_MEASURES();

var area_data = new AREA_MEASURES();

var press_data = new PRESS_MEASURES();


function checkNum(str)
{
  for (var i=0; i<str.length; i++)
  {
    var ch = str.substring(i, i + 1)
    
    if (ch!="." && ch!="+" && ch!="-" && ch!="e" && ch!="E" && (ch < "0" || ch > "9"))
    {
      alert("Please enter a valid number.");
      return false;
    }
  }
  return true
}


function normalize(what,digits)
{
  var str=""+what;
  
  var pp=Math.max(str.lastIndexOf("+"),str.lastIndexOf("-"));
  
  var idot=str.indexOf(".");
  
  if (idot>=1)
  {
    var ee=(pp>0)?str.substring(pp-1,str.length):"";
    
    digits+=idot;
    
    if (digits>=str.length)
      return str;
      
    if (pp>0 && digits>=pp)
      digits-=pp;
      
    var c=eval(str.charAt(digits));
    
    var ipos=digits-1;
    
    if (c>=5)
    {
      while (str.charAt(ipos)=="9")
        ipos--;
        
      if (str.charAt(ipos)==".")
      {
        var nc=eval(str.substring(0,idot))+1;
        
        if (nc==10 && ee.length>0)
        {
          nc=1;
          ee="e"+(eval(ee.substring(1,ee.length))+1);
        }
        return ""+nc+ee;
      }
      return str.substring(0,ipos)+(eval(str.charAt(ipos))+1)+ee;
      
    }
    else
      var ret=str.substring(0,digits)+ee;

    for (var i=0; i<ret.length; i++)
        if (ret.charAt(i)>"0" && ret.charAt(i)<="9")
          return ret;

    return str;
  }
  return str;
}


function compute(obj,val,data)
{
  if (obj[val].value)
  {
    var uval=0;
    
    uval = obj[val].value*data[val];
    
    if( (uval >= 0) && (obj[val].value.indexOf("-") != -1) )
    {
      uval = -uval;    // *** Hack for Opera 4.0  2000-10-14
    }

    for (var i in data)
      obj[i].value=normalize(uval/data[i],8);
  }
}


function computeTempC(obj)
{
  var tempC = parseFloat(obj.tempCelsius.value)

  if( (tempC >= 0) && (obj.tempCelsius.value.indexOf("-") != -1) )
  {
    tempC = -tempC;    // *** Hack for Opera 4.0  2000-10-14
  }

  if(!(tempC < -273.15) )
  {
    var tempK = tempC + 273.15

    var tempF = 32 + (tempC * 9 / 5)

    obj.tempKelvin.value = tempK

    obj.tempFahr.value = tempF
  }

  else
  {                                  // **** BJ 2000-10-14
    obj.tempKelvin.value = "ERROR"

    obj.tempFahr.value = "ERROR"
  }
}

function computeTempK(obj)
{
  var tempK = parseFloat(obj.tempKelvin.value)

  if( (tempK >= 0) && (obj.tempKelvin.value.indexOf("-") != -1) )
  {
    tempK = -tempK;    // *** Hack for Opera 4.0  2000-10-14
  }

  if(!(tempK < 0) )
  {
    var tempC = tempK - 273.15

    var tempF = 32 + (tempC * 9 / 5)

    obj.tempCelsius.value = tempC

    obj.tempFahr.value = tempF
  }
  else
  {                                  // **** BJ 2000-10-14
    obj.tempCelsius.value = "ERROR"

    obj.tempFahr.value = "ERROR"
  }
}

function computeTempF(obj)
{
  var tempF = parseFloat(obj.tempFahr.value)

  if( (tempF >= 0) && (obj.tempFahr.value.indexOf("-") != -1) )
  {
    tempF = -tempF;    // *** Hack for Opera 4.0  2000-10-14
  }

  if(!(tempF < -459.666666) )
  {
    var tempC = (tempF - 32) * 5 / 9

    var tempK = tempC + 273.15

    obj.tempCelsius.value = tempC

    obj.tempKelvin.value = tempK
  }

  else
  {                                  // **** BJ 2000-10-14
    obj.tempCelsius.value = "ERROR"

    obj.tempKelvin.value = "ERROR"
  }
}


function resetValues(form,data)    // *** Hack for Opera 4.0  2000-10-14
{
    for (var i in data)
      form[i].value="";
}


function resetAll(form)    // *** Hack for Opera 4.0  2000-10-14
{
  resetValues(form,vol_data);
  resetValues(form,weight_data);
  resetValues(form,length_data);
  resetValues(form,area_data);
  resetValues(form,press_data);

  form.tempCelsius.value = ""
  form.tempKelvin.value = ""
  form.tempFahr.value = ""
}

//* * * * * * * *   CONVERT SCRIPT - END -  * * * * * * * * *