Returns the index within the specified vector of the first occurence of the
given object, starting at the specified index, and testing for equality using the
Java java.lang.Object.equals() method.
Returns -1 if the object is not found.
Parameters:
v
Note: The null value passed in this parameter
will cause an error.
obj
If this parameter is null, the function
will seek the first occurence of null element.
fromIndex
lastIndexOf()
You may call this function in a method-like style:
v.indexOf(obj,fromIndex)