// JavaScript Document
<!-- 

 function getmes(fecha){

  var mes = fecha.getMonth();

  switch(mes){

   case 0: return "enero";

   case 1: return "febrero";

   case 2: return "marzo";

   case 3: return "abril";

   case 4: return "mayo";

   case 5: return "junio"; 

   case 6: return "julio";

   case 7: return "agosto";

   case 8: return "septiembre";

   case 9: return "octubre";

   case 10: return "noviembre";

   case 11: return "diciembre";
  }  
 }
function IsNum( numstr ) {
	// Return immediately if an invalid value was passed in
	if (numstr+"" == "undefined" || numstr+"" == "null" || numstr+"" == "")	
		return false;

	var isValid = true;
	var decCount = 0;		// number of decimal points in the string

	// convert to a string for performing string comparisons.
	numstr += "";	

	// Loop through string and test each character. If any
	// character is not a number, return a false result.
 	// Include special cases for negative numbers (first char == '-')
	// and a single decimal point (any one char in string == '.').   
	for (i = 0; i < numstr.length; i++) {
		// track number of decimal points
		if (numstr.charAt(i) == ".")
			decCount++;

    	if (!((numstr.charAt(i) >= "0") && (numstr.charAt(i) <= "9") || 
				(numstr.charAt(i) == "-") || (numstr.charAt(i) == "."))) {
       	isValid = false;
       	break;
		} else if ((numstr.charAt(i) == "-" && i != 0) ||
				(numstr.charAt(i) == "." && numstr.length == 1) ||
			  (numstr.charAt(i) == "." && decCount > 1)) {
       	isValid = false;
       	break;
      }         	         	       
//if (!((numstr.charAt(i) >= "0") && (numstr.charAt(i) <= "9")) || 
   } // END for   
   
   	return isValid;
}  // end IsNum

function trim(inputString) {
   // Removes leading and trailing spaces from the passed string. Also removes
   // consecutive spaces and replaces it with one space. If something besides
   // a string is passed in (null, custom object, etc.) then return the input.
   if (typeof inputString != "string") { return inputString; }
   var retValue = inputString;
   var ch = retValue.substring(0, 1);
   while (ch == " ") { // Check for spaces at the beginning of the string
      retValue = retValue.substring(1, retValue.length);
      ch = retValue.substring(0, 1);
   }
   ch = retValue.substring(retValue.length-1, retValue.length);
   while (ch == " ") { // Check for spaces at the end of the string
      retValue = retValue.substring(0, retValue.length-1);
      ch = retValue.substring(retValue.length-1, retValue.length);
   }
   while (retValue.indexOf("  ") != -1) { // Note that there are two spaces in the string - look for multiple spaces within the string
      retValue = retValue.substring(0, retValue.indexOf("  ")) + retValue.substring(retValue.indexOf("  ")+1, retValue.length); // Again, there are two spaces in each of the strings
   }
   return retValue; // Return the trimmed string back to the user
} // Ends the "trim" function


function valida(myform)
{
	if ((trim(myform.usuario.value)!="") &&  (trim(myform.clave.value)!=""))
		return(true)
	else	
	 return (false)
}
function CargarFoto(img, ancho, alto){
  derecha=(screen.width-ancho)/2;
  arriba=(screen.height-alto)/2;
  string="toolbar=0,scrollbars=0,location=0,statusbar=0,menubar=0,resizable=1,width="+ancho+",height="+alto+",left="+derecha+",top="+arriba+"";
  fin=window.open(img,"",string);
}
// -->