John K Budnik

US Patent:

6087967, Jul 11, 2000

Filed:

Sep 3, 1998

Appl. No.:

9/146106

Inventors:

John Budnik - New Paltz NY
John R. Krauss - Carmel NY

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

H03M 746
G06F 300

US Classification:

341 63

Abstract:

A method for creating a file of compressed data representing trace events produced in a circuit simulation. The method creates first and second arrays of value changes for a facility being monitored, and the time of the changes. The first and second arrays of data are compressed by identifying any data forming a repeating pattern, by the pattern and an iteration count. Each of these arrays have a common index, representing the position data for a facility as changed. Facility names are also compressed using a hashing algorithm which stores an index based on the hash result. The reproduction of the compressed data occurs without expanding the entire data file, by locating stored data by the facility name index which points to the position in the file of the stored facility data. The data is reviewed based on an inquiry which selects particular time intervals, which may be retrieved from the file along with the related values.