describe polarized light Mueller calculus, used in optics to handle Stokes vectors, which describe the polarization of incoherent light Operational calculus, used to solve differential equations arising in electronics Formal language Lambda calculus, a formulation of the theory of reflexive functions that has deep connections to computational theory Kappa calculus, a reformulation of the first-order fragment of typed lambda calculus Rho calculus, introduced as a general means to uniformly integrate rewriting into lambda calculus Process calculus, a set of approaches to formulating formal models of concurrent systems Ambient calculus, a family of models for concurrent systems based on the concept of agent mobility Join calculus, a theoretical model for the design of distributed programming languages π-calculus, a formulation of the theory of concurrent, communicating processes Relational calculus, a calculus for the relational data model Domain relational calculus Tuple calculus Refinement calculus, a way of refining models of programs into efficient programs Other meanings Battlefield calculus, military calculation of all known factors into the decision-making and action-planning process Calculus of negligence, a legal standard in U.S. tort law to determine if a duty of care has been breached Felicific calculus, a procedure to evaluate the benefit of an action, according to Bentham Professor Calculus, a fictional character in the comic-strip series The Adventures of Tintin