• Corpus ID: 237490954

Restriction in Program Algebra

  title={Restriction in Program Algebra},
  author={Marcel Jackson and Tim Stokes},
intersection, ∩: f ∩ g = {(x, y) ∈ X × Y | (x, y) ∈ f and (x, y) ∈ g} and difference, \: f\g = {(x, y) ∈ X × Y | (x, y) ∈ f and (x, y) 6∈ g}. Before we proceed further, we note that the surrounding literature contains a number of conflicting notations for the operations just introduced. In [2], the operation we have denoted ◦ is referred to in an equivalent form as “intersection”, with definition and notation f@g := g ◦ f . The notation for ⊔ in [2] is ⊲, however, the notation ⊲ is well… 


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