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The clock must be either hybrid or real. Under a hybrid clock, the date never changes unless specifically altered or unless the suite restarts, either automatically or from a begin command. Under a real clock, the date advances by one day at midnight. Time and date dependencies work a little differently under the two clocks. The default clock type is hybrid real.
Clock gain is expressed in seconds and can be given as an integer, a time or a date. Seconds and time can have a sign:
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