function deleteByIndex(myArray,index) {
  //showArray(myArray, "before");
  myArray.splice(index,1);
  //showArray(myArray, "after");
  return myArray;
}

function deleteByValue(myArray,value) {
  //showArray(myArray, "before");
  mylength = myArray.length;
  i = 0;
  do {
    if (myArray[i] == value) {
      return myArray.splice(i,1);
    }
    i++;
  } while (i<mylength);
}

function showArray(what, title) {
  myString = (title) ? title : "";
  if (what) {
    items = what;
    for (i in items) {
      myString += i + "=" + items[i] + "\n";
    }
  }
  alert(myString);
}

function getIndexByValue(myArray,value) {
  mylength = myArray.length;
  i = 0;
  do {
    if (myArray[i] == value) {
      return i;
    }
    i++;
  } while (i<mylength);
}

function inArray(myArray,value) {
  mylength = myArray.length;
  i = 0;
  do {
    if (myArray[i] == value) {
      return true;
    }
    i++;
  } while (i<mylength);
  return false;
}