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One way is to use alarm and AlarmInerrupt:

sage: from cysignals.alarm import alarm, AlarmInterrupt, cancel_alarm

If computation takes more than 5 seconds, computation is stopped:

sage: try:
....:     alarm(5)
....:     factor(2^1000-1)
....: except AlarmInterrupt:
....:     print('opps, timed out!')
....: else:
....:     cancel_alarm()
....:     
opps, timed out!

If computation takes less than 5 seconds, it is not stopped:

sage: try:
....:     alarm(5)
....:     factor(2^100-1)
....: except AlarmInterrupt:
....:     print('opps, timed out!')
....: else:
....:     cancel_alarm()
....:     
3 * 5^3 * 11 * 31 * 41 * 101 * 251 * 601 * 1801 * 4051 * 8101 * 268501

It is important to cancel the alarm if the computation succeeds (as done above in the else clause) or otherwise the AlarmInterrupt will be raised later on.

One way is to use alarm and AlarmInerrupt:

sage: from cysignals.alarm import alarm, AlarmInterrupt, cancel_alarm

If computation takes more than 5 seconds, computation is stopped:

sage: try:
....:     alarm(5)
....:     factor(2^1000-1)
....: except AlarmInterrupt:
....:     print('opps, timed out!')
....: else:
....:     cancel_alarm()
....:     
opps, timed out!

If computation takes less than 5 seconds, it is not stopped:

sage: try:
....:     alarm(5)
....:     factor(2^100-1)
....: except AlarmInterrupt:
....:     print('opps, timed out!')
....: else:
....:     cancel_alarm()
....:     
3 * 5^3 * 11 * 31 * 41 * 101 * 251 * 601 * 1801 * 4051 * 8101 * 268501

It is important to cancel the alarm if the computation succeeds (as done above in the else clause) or otherwise the AlarmInterrupt will be raised later on.

#!/usr/bin/env sage

from sage.all import *
from cysignals.alarm import alarm, AlarmInterrupt, cancel_alarm

var('x a b')

def doTheIntegration():
    integrand = tan(x)/(a^3+b^3*tan(x)^2)^(1/3)

    fricas.setSimplifyDenomsFlag(fricas.true)
    anti=integrate(integrand,x,algorithm="fricas")                        
    return anti

try:
    alarm(20)        
    anti = doTheIntegration()        
except (AlarmInterrupt,KeyboardInterrupt):      
    print("Timed out")
else:
    print("Completed OK, anti=",anti)
    cancel_alarm()