This function is generic; method functions can be written to handle
specific classes of objects. By default, it tries to extract a
needUpdate attribute of object. If this is NULL
or FALSE it returns FALSE; else it returns TRUE.
Updating of objects usually takes place in iterative algorithms in
which auxiliary quantities associated with the object, and not being
optimized over, may change.
Usage
needUpdate(object)
Value
a logical value indicating whether object needs to be updated.