One of the advantages of prototype-based languages is that they provide self-sufficient objects which do not depend on classes or other objects for their definitions. But objects can refer to other objects, and the effects of these inter-object references introduce arbitrary, uncontrolled dependencies between objects. We propose adding an explicit notion of object ownership to control dependenc...

This paper describes an empirical comparison of the e ectiveness of six context-insensitive pointer analysis algorithms that use varying degrees of ow-sensitivity. Four of the algorithms are ow-insensitive, one is ow-sensitive, and another is ow-insensitive, but uses precomputed ow-sensitive information. The e ectiveness of each analysis is quanti ed in terms of compile-time e ciency and precis...

Interprocedural data flow information IS useful for many software testing and analysis techniques, including data flow testing, regression testing, program slicing, and impact analysis. For programs with aliases, these testing and analysis techniques can yield invalid results, unless the data flow information accounts for aliasing effects. Recent research provides algorithms for performing inte...

An unshared object can be accessed without regard to possible connicts with other parts of a system, whether concurrent or single-threaded. A unique variable (sometimes known as a \free" or \linear" variable) is one that either is null or else refers to an unshared object. Being able to declare and check which variables are unique improves a pro-grammer's ability to avoid program faults. In pre...

this paper  considersthe problem of  aliasing in information processing. the cubic spline method of interpolating the uniformly sampled signals and its effects on the autocorrelation estimation as well as the resulting spectral density function are studied by simulating random signals with known autocorrelation functions. hence, by comparison of aliased and alias-free cases, indications are ded...

A crucial problem facing both human and artificial RL agents is correctly perceiving, and interpreting, the current state of the environment. For instance, imagine a traveler staying in an unfamiliar hotel, with each floor and exit decorated identically. Based on perceptual information alone, this guest might experience difficulty learning how to navigate towards his room, since the various hal...

We show that the two-dimensional one pulse (TOP) representation of magic-angle spinning nuclear magnetic resonance data of half-integer quadrupolar nuclei has significant advantages over the conventional one-dimensional spectrum. The TOP spectrum, which correlates NMR frequency to spinning sideband order, provides a rapid determination of the number of sites as well as the size of the their qua...

A central methodological problem in programming with multiple levels of abstractions is the loosely defined problem of rep exposure. This paper traces the problem of rep exposure to the precisely defined notion of abstract aliasing. The paper also outlines a statically-enforceable discipline for avoiding abstract aliasing, but the outline is incomplete.

Reasoning about object-oriented programs requires an appropriate technique to reflect a fundamental “general relativity” property of the approach: every operation is relative to a current object, which changes with every qualified call; such a call needs access to the context of the client object. The notion of negative variable, discussed in this article, provides a framework for reasoning abo...