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             |                            Welcome to tnorm!                         
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             |         To get started, enter the name of a manifold in the          
             +-------- Manifold field, and click Load. Any string accepted          
                       by SnapPy is accepted here, e.g., '4_1', 'DT:[(6,8,2,4)]',  
                       'L5a1' (without quotes). To open a file containing a 
                       triangulation (with extention .tri), type 'file' and 
                       click Load.                                       
                                                                                                       
                       After loading a manifold, click the 'norm ball' or           
                       'dual norm ball' tabs to view more detailed information      
                       about each, or click on the 'qton surfaces' tab to view 
                       information about all transversely oriented normal
                       surfaces (not just vertices of the norm ball). Buttons
                       at left give additional information about the norm ball.

                       In the case where the Thurston norm is a semi-norm (and 
                       not a norm), e.g., this can happen if the manifold is not 
                       hyperbolic, things may go wrong. You should not trust the 
                       results of such computations, though they might be correct 
                       for some manifolds. When tnorm IS able to compute the norm 
                       ball, it is a non-compact polyhedron, so we can only graph 
                       its projection to the subspace in which it is a norm. We 
                       also give the option in this case of viewing the convex hull 
                       of the image in H2 of normal surfaces having negative Euler
                       characteristic (this is a finite polyhedron).


