is an option for various functions that specifies the maximum time to spend doing a particular operation.


  • TimeConstraint->t specifies that a maximum of t seconds of CPU time should be spent doing a particular operation, or trying a particular transformation or part of an algorithm.
  • TimeConstraint->Infinity specifies that there should be no limit on the CPU time allowed.
  • In functions such as Simplify and FullSimplify, settings for TimeConstraint give only the maximum time to be spent doing a particular transformation on a particular subpart; the total time spent processing the whole expression may be considerably larger.
  • Changing the setting for TimeConstraint will never affect the validity of a result obtained from functions like Simplify or FullSimplify, but smaller settings may prevent the simplest possible form from being found.
  • Since different computer systems run at different speeds, the same setting for TimeConstraint can lead to different results on different systems.


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Basic Examples  (2)

This takes a long time, due to trigonometric expansion, but does not yield a simplification:

TimeConstraint limits the time spent on any single transformation:

A similar example, where the transformation yields a simplification:

In this case, setting TimeConstraint prevents some simplification:

Scope  (1)

Checking whether a condition follows from assumptions may take a long time:

If a condition does not follow from assumptions, checking this may still take a long time:

The time spent on a single condition check is restricted by the value of TimeConstraint:

With a time constraint of one second, Refine cannot prove that :

Introduced in 1996