NASA logo

+ Contact NASA



  • + HOME
  • + WELCOME
  • + QUICK PAGE
  • + PHILOSOPHY
  • + TEAM
  • + RESEARCH
  • + LINKS

  • Top File of PVS metric_space Library

     
    %------------------------------------------------------------------------------
    % Metric Spaces
    %
    %     Author: David Lester, Manchester University
    %
    % All references are to WA Sutherland "Introduction to Metric and
    % Topological Spaces", OUP, 1981
    %
    %     Version 1.0            17/08/07  Initial Version
    %
    % Note that an alternate version of metric spaces is available in the analysis
    % library.  See
    %
    %    metric_spaces[T:TYPE+,d:[T,T->nnreal]]: THEORY
    %    BEGIN
    %
    %      ASSUMING IMPORTING metric_spaces_def[T,d]
    %          fullset_metric_space: ASSUMPTION metric_space?[T,d](fullset[T])
    %      ENDASSUMING
    %
    % This version does not use the topology library.
    %------------------------------------------------------------------------------
    
    top: THEORY
    
    BEGIN
    
      IMPORTING
    % Extra results
        countable_cross,   % the cross product of two countable sets is countable
    
    % Basic properties
        metric_def,        % Definition of metric
        metric_space_def,  % Basic properties of metric spaces
        metric_space,      % Deeper results
        submetric_def,     % metrics for sub-spaces
        metric_subspace,   % subspaces of metric spaces
        complete_product,  % products of complete metrics
    
    % Continuity in metric spaces
        metric_continuity, % Continuity expressed using metrics (epsilon/delta)
        composition_continuous,
                           % composition is continuous
        composition_uniform_continuity,
                           % composing uniform continuous functions
    
    % Convergence properties
        convergence_aux,   % Properties of convergence in metric spaces
    
    % real topology results
        real_topology,     % The topology of the reals
        heine_borel_scaf,  % Foundations for ...
        heine_borel,       % Heine-Borel
        euclidean,         % Topology of R^n (Vector[n])
        real_continuity,   % Continuity of functions [T->real]
    %%%%%%%%%%%%%% RWB %%%%%%%%%%%%% <. %%%%%%%%%%%%%    
        continuity_link,   % Linking continuity with that in the analysis library
        continuity_subspace, % Continuity on subspaces
        test_cont          % A surprising, but correct result: 1/x is continuous 
                           % (provided that the domain is taken to be the metric space
                           % induced topology restricted to the nonzero reals.)
    
    END top
    

    The tag [*] identifies links that are outside the NASA domain