19. A programmed computer system as defined in claim 13, wherein said second means is also responsive to time durational threshold values stored in said data structure.
13. In a programmed computer system for recognizing human speech patterns in response to analog signals identifying the frequency of said analog signals, a data structure for comparing said speech patterns with stored templates, comprising: a. first means in said data structure and responsive to said analog signals for storing first coded signals indicative of the average frequency of said analog signals during successive time intervals; b. second means in said data structure responsive to said first coded signals for comparing said first coded signals with count threshold values stored in said data structure to identify a frequency characteristic of said analog signals corresponding to the existence of fricative-like, vowel-like, and silence intervals during each of said successive time intervals; c. third means in said data structure for varying said count threshold values in response to a previous state of said analog signal frequency characteristic; d. fourth means in said data structure responsive to said time interval frequency characteristic for storing a coded signal indicative of the number of successive time intervals having an identical frequency characteristic; e. fifth means in said data structure and responsive to said fourth means for storing coded signals indicative of groups of successive time intervals with an identical frequency characteristic which exceed, in number, a value stored as a coded signal in said data structure; f. sixth means in said data structure storing coded signals indicative of recognition templates; and g. seventh means in said data structure for comparing said coded signals stored by said fifth means with said coded signals stored by said sixth means.