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Hash Function

Zoltan provides a hash function for global and local IDs. The hash function computes a non-negative integer value in a certain range from an ID.
Zoltan_Hash  : hash a global or local ID into non-negative integers
unsigned int Zoltan_Hash( ZOLTAN_ID_PTR key, int num_id_entries, unsigned int n); 
Zoltan_Hash computes a hash value for a global or local ID. Note that this hash function has been optimized for 32-bit integer systems, but should  work on any machine. The current implementation uses a simple multiplicative hash function based on Don Knuth's golden ratio method; see The Art of  Computer Programming, vol. 3.
 
Arguments:
    key A pointer to the ID to be hashed.
    num_id_entries The length of the ID (as given by NUM_GID_ENTRIES or NUM_LID_ENTRIES).
    n The computed hash value will be between 0 and n-1. 
Return Value:
    unsigned int The hash value (between 0 and n-1). 


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