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Re: [Q] Problem with combinatorica

• To: mathgroup@smc.vnet.net
• Subject: [mg11007] Re: [Q] Problem with combinatorica
• From: Allan Hayes <hay@haystack.demon.co.uk>
• Date: Mon, 16 Feb 1998 18:15:15 -0500
• References: <6c8prf$aqc@smc.vnet.net>

Konopnicki David wrote:
>  ... I defined
> the following function:
> CG[n_,p_] :=
> While[True,
>        g := RandomGraph[n,p,Directed];
>       If[ConnectedQ[g,Directed], g; Break[]] ]

> However, it doesn't work and I don't know why.

David:

You are not getting the value of g out. The following versions work:

CG[n_,p_] := 
(While[True,
       g := RandomGraph[n,p,Directed];
      If[ConnectedQ[g,Directed], g; Break[]] ];g) (*final g added*)

CG[n_,p_] := 
Catch[While[True,
       g := RandomGraph[n,p,Directed];
      If[ConnectedQ[g,Directed], Throw[g] ]]]

CG[n_,p_] := 
FixedPoint[RandomGraph[n,p,Directed]&,1, SameTest -> (ConnectedQ[#2]&)]


-- 
Allan Hayes
Training and Consulting
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hay@haystack.demon.co.uk
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