Patent Document ID: 5390286
Application ID: 07499039
Patent Flag: 1

Claim One:
1. An expert system for evaluating an expression comprising a plurality of ordered conditions, each condition in the expression being linked and related to the next condition in the order by one of a preselected set of logical operators, the evaluation of the expression being based upon values of data elements presented to the expert system the expert system comprising: (a) a plurality of nodes, each of the nodes representing one of the conditions of the expression, the plurality of nodes being coupled in such a manner to represent the order and logical relationships of the conditions in the expression; (b) a processor coupled to the plurality of nodes for accepting as input a series of the values of data elements, for passing the values of data elements to the nodes of the expert system for utilizing each node to test the condition it represents as a success or failure based on the values of data elements, and pass information on successful tests to other related nodes, and for evaluating the expression based on the results of the node tests; (c) at least one of the plurality of nodes being coupled to a memory for storing the results of condition testing in that node; and (d) the at least one of the plurality of nodes having its condition satisfied on the successful completion of two tests, the first test requiring that a value of data elements satisfies the condition represented by the at least one of the plurality of nodes, the second test requiring that the value of a previous one of the data elements stored in the memory did not satisfy the condition of the expression.