This is documentation for Mathematica 8, which was
based on an earlier version of the Wolfram Language.
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represents an object whose value in a Dynamic should be refreshed at times specified by the options opts.
Refresh[expr, None]
specifies that the value of expr should never automatically be refreshed.
  • The following options can be given:
TrackedSymbolsAutomaticsymbols whose changes trigger an update
UpdateIntervalInfinitytime interval at which to do updates
  • When Refresh is evaluated inside a Dynamic, it gives the current value of expr, then specifies criteria for when the Dynamic should be updated.
  • When one Refresh appears inside another, the innermost Refresh takes precedence.
  • The setting UpdateInterval->t specifies that updating should be done at least every t seconds.
Make a dynamically updating clock:
Make a dynamically updating clock:
Click for copyable input
By default, Dynamic updates as fast as possible:
Control the update using TrackedSymbols and UpdateInterval:
Update only when updates in a Manipulate:
Use UpdateInterval to specify how often should update:
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