In STATLIB (http://lib.stat.cmu.edu), F.Mutagh's implementation (Fortran 77) for hierarchical clustering http://lib.stat.cmu.edu/multi/hcl.
This programme is very efficient: O(n^2) time, O(n^2) space and includes Ward's method.
It's very easy to translate this programme in C++ code.
Example: http://sapc34.rdg.ac.uk/~andrew/bioinf.org/software/cluster/index.html

Gilles


A 08:37 12/11/2002 -0800, Jason Harrison a écrit :
>On Tuesday, November 12, 2002, at 07:36  AM, shannon wrote:
>>Is code avaialble to implement Ward's method in S-Plus?
>
>While we're on the topic, is there an implementation of Ward's method
>and PEST in C/C++?
>
>-Jason
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