Programming with Algebraic Effects and Handlers

Eff is a programming language based on the algebraic approach to computational effects, in which effects are viewed as algebraic operations and effect handlers as homomorphisms from free algebras. Eff supports first-class effects and handlers through which we may easily define new computational effects, seamlessly combine existing ones, and handle them in novel ways. We give a denotational semantics of eff and discuss a prototype implementation based on it. Through examples we demonstrate how the standard effects are treated in eff, and how eff supports programming techniques that use various forms of delimited continuations, such as backtracking, breadth-first search, selection functionals, cooperative multi-threading, and others

Index to Library Trends Volume 38

published or submitted for publicatio

Superiority of one-way and realtime quantum machines and new directions

In automata theory, the quantum computation has been widely examined for finite state machines, known as quantum finite automata (QFAs), and less attention has been given to the QFAs augmented with counters or stacks. Moreover, to our knowledge, there is no result related to QFAs having more than one input head. In this paper, we focus on such generalizations of QFAs whose input head(s) operate(s) in one-way or realtime mode and present many superiority of them to their classical counterparts. Furthermore, we propose some open problems and conjectures in order to investigate the power of quantumness better. We also give some new results on classical computation.Comment: A revised edition with some correction

Rigorous Multiple-Precision Evaluation of D-Finite Functions in SageMath

We present a new open source implementation in the SageMath computer algebra system of algorithms for the numerical solution of linear ODEs with polynomial coefficients. Our code supports regular singular connection problems and provides rigorous error bounds

Measuring inequality in a cross-tabulation with ordered categories: from the Gini coefficient to the Tog coefficient

This paper introduces the Tog coefficient, which can be used to measure the level of inequality in a cross-tabulation of two ordinal-level variables. The Gini coefficient is a standard measure of income inequality which has been adapted by other authors for use in different contexts such as the measurement of health inequalities and the quantification of occupational segregation; the Tog coefficient represents a further stage in this process of development. The paper outlines the construction of the Tog coefficient and illustrates this using a social mobility table based on data from the 1972 Oxford Mobility Study. The trend in social mobility-related inequality as measured by the Tog coefficient is compared with the findings of Goldthorpe et al. based on odds ratios. A more elaborate application of the Tog coefficient uses a variety of data relating to the similarity of spouses' class backgrounds to demonstrate the existence of a long-term decline in the level of inequality in British society