function isRUC(valor){
	suma = 0;
	x = 6;
	for(var i=0;i < valor.length-1;i++){
	  if ( i == 4 ) x = 8
	  digito = valor.charAt(i) - "0";
	  x = x - 1
	  if ( i==0 ) suma += (digito*x)
	  else suma += (digito*x)
	}
	resto = suma % 11;
	resto = 11 - resto
      
	if ( resto >= 10) resto = resto - 10;
	if ( resto == valor.charAt( valor.length-1 ) - "0" ){
	  return 0
	}      
	return -1
}
			
function isEmail (s)
{
    for (i = 0; i < s.length; i++)
    {
        var c = s.charAt(i);
		if (c == " ") return -1;
    }
    var i = 1;
    var sLength = s.length;
    while ((i < sLength) && (s.charAt(i) != "@"))
    { i++
    }
    if ((i >= sLength) || (s.charAt(i) != "@")) return -1;
    else i += 2;
    var cont = 0
    while (i < sLength)
    {
       var c = s.charAt(i);
       if (c == ".") cont++
	   i++
    }
 if ((cont == 0) || (cont > 3)) return -1
 else return 0
}


function rtrim(str)
{
   return str.replace(/[ ]+$/, "");
}


function ltrim(str) 
{ 
return str.replace(/^[ ]+/, ""); 
}