Daylight v4.9
Release Date: 1 February 2008


dt_uid - find the 'unique ID' of an object

Generic Prototype

dt_uid(dt_Handle) => dt_Integer

C Prototype

#include "dt_smiles.h"

dt_Integer dt_uid(dt_Handle object)

FORTRAN Prototype

include ''

integer*4 dt_f_uid(object)

integer*4 object


Finds the 'unique ID' (uid) of the object within its containing object. For molecules, 'object' must be an atom, bond, or cycle.

The containing object is its parent object. A unique ID is a smallish non-negative integer (it can be zero) that is guaranteed to be associated with 'object' for as long as 'object' exists within the parent object.

Note that uids are only unique across a single containing object; for example, arbitrary atoms from two different molecules may have the same uids. Similarly, uids are only unique across a single type of object within a single molecule.

Uids are intended to be small, dense integers. For this reason, uids make good array indices (where handles do not).

Return Value

Returns the integer uid. For objects other than those mentioned above, property is defined as -1.

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