A method of determining candidate patterns from a set of patterns of a patterning process. The method includes obtaining (i) a set of patterns of a patterning process, (ii) a search pattern having a first feature and a second feature, and (iii) a search condition comprising a relative position between the first feature and the second feature of the search pattern; and determining a set of candidate patterns from the set of patterns that satisfies the search condition associated with the first feature and the second feature of the search pattern.