var strCaller="";
function gRegister(strFunctionCall){
  strCaller=strFunctionCall;
  return true;
}
function gUnregister(){
  strCaller="";
  return true;
}

function gIsNumber(strNumber,strMin,strMax){
/**
 *gIsNumber(strNumber,strMin,strMax)
 *strMin and strMax may be null.
 *if strMin and/or strMax are not null, all are verified as numbers,
 *and strMin<=strNumber and/or strNumber<=strMax
 */
  gRegister("gIsNumber");
  var strTempNumber=strNumber;  //make a copy
  strTempNumber=""+strTempNumber; //make sure copy is string
  if(strTempNumber.length==0) return false;
  for(i=0;i<strTempNumber.length;i++){
    if(!((strTempNumber.charAt(i)=="0")||
      (strTempNumber.charAt(i)=="1")||
      (strTempNumber.charAt(i)=="2")||
      (strTempNumber.charAt(i)=="3")||
      (strTempNumber.charAt(i)=="4")||
      (strTempNumber.charAt(i)=="5")||
      (strTempNumber.charAt(i)=="6")||
      (strTempNumber.charAt(i)=="7")||
      (strTempNumber.charAt(i)=="8")||
      (strTempNumber.charAt(i)=="9")||
      (strTempNumber.charAt(i)=="-")||
      (strTempNumber.charAt(i)=="."))){
      return false;
    }
  }
  if(strTempNumber.indexOf(".")!=-1){
    var strDecident=strTempNumber.substr(strTempNumber.indexOf("."));
    var blnBadDecident=false;
    if(strDecident==".") blnBadDecident=true;
    for(i=1;i<strDecident.length;i++){
      if((strDecident.charAt(i)==".")||
        (strDecident.charAt(i)=="-")){
        blnBadDecident=true;
      }
    }
    if(blnBadDecident){
      return false;
    }
  }

  if ( strTempNumber.indexOf("-") != -1 ) {  //if it includes a - test:
    if ( strTempNumber.length == 1 ) return false;        //bad if - is the only character
    if ( strTempNumber.indexOf("-") != 0 ) return false;  //bad if - is not the first character
  }

  if(strMin){
    var strTempMin=strMin;
    strTempMin=""+strTempMin;
    if(strTempMin.length==0) return false;
    for(i=0;i<strTempMin.length;i++){
      if(!((strTempMin.charAt(i)=="0")||
        (strTempMin.charAt(i)=="1")||
        (strTempMin.charAt(i)=="2")||
        (strTempMin.charAt(i)=="3")||
        (strTempMin.charAt(i)=="4")||
        (strTempMin.charAt(i)=="5")||
        (strTempMin.charAt(i)=="6")||
        (strTempMin.charAt(i)=="7")||
        (strTempMin.charAt(i)=="8")||
        (strTempMin.charAt(i)=="9")||
        (strTempMin.charAt(i)=="-")||
        (strTempMin.charAt(i)=="."))){
        return false;
      }
    }
    if(strNumber<parseFloat(strMin)) return false;
  }
  if(strMax){
    var strTempMax=strMax;
    strTempMax=""+strTempMax;
    if(strTempMax.length==0) return false;
    for(i=0;i<strTempMax.length;i++){
      if(!((strTempMax.charAt(i)=="0")||
        (strTempMax.charAt(i)=="1")||
        (strTempMax.charAt(i)=="2")||
        (strTempMax.charAt(i)=="3")||
        (strTempMax.charAt(i)=="4")||
        (strTempMax.charAt(i)=="5")||
        (strTempMax.charAt(i)=="6")||
        (strTempMax.charAt(i)=="7")||
        (strTempMax.charAt(i)=="8")||
        (strTempMax.charAt(i)=="9")||
        (strTempMax.charAt(i)=="-")||
        (strTempMax.charAt(i)=="."))){
        return false;
      }
    }
    if(strNumber>parseFloat(strMax)) return false;
  }
  gUnregister();
  return true;
}

function gMakeNumber(strNumber,strAltValue){
/**
 *gMakeNumber(strNumber,strAltValue)
 *If strNumber is a number, returns strNumber
 *else returns strAltValue
 */
  if(gIsNumber(strNumber)) return parseInt(strNumber)
  else return strAltValue;
}
function gToInches(strFeet,strInches,strMin,strMax){
/**
 *gToInches(strFeet,strInches,strMin,strMax)
 *strMin and strMax may be null.  If not, they should be inches values.
 *if strMin and/or strMax are not null, all are converted to inches,
 *and strMin<=strDate and/or strDate<=strMax
 */
  gRegister("gToInches");
  if(!gIsNumber(strFeet)) return false;
  if(!gIsNumber(strInches)) return false;
  strInches+=(strFeet*12);
  if(strMin){
  if(!gIsNumber(strMin)) return false;
      if(strInches<strMin) return false;
  }
  if(strMax){
  if(!gIsNumber(strMax)) return false;
  if(strInches>strMax) return false;
  }
  gUnregister();
  return strInches;
}

function gToFeetAndInches(strInches,strMin,strMax){
/**
 *gToFeetAndInches(strInches,strMin,strMax)
 *strMin and strMax may be null.
 *if strMin and/or strMax are not null, return a string of x'y",
 *where x=feet and y=inches,
 *and strMin<=strDate and/or strDate<=strMax
 */
  gRegister("gToFeetAndInches");
  if(!gIsNumber(strInches)) return false;
  if(strMin){
  if(!gIsNumber(strMin)) return false;
      if(strInches<strMin) return false;
  }
  if(strMax){
  if(!gIsNumber(strMax)) return false;
  if(strInches>strMax) return false;
  }
  var strReturnValue='';
  strReturnValue=(strInches-(parseInt(strInches)%12))/12+'\''+(parseInt(strInches)%12)+'"';
  gUnregister();
  return strReturnValue;
}