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asked 2020-03-23 20:22:35 +0100

Nasser gravatar image

can one now set a timelimit on operation in sagemath?

I have found serious bug related to my own way of doing timeout when using sagemath. Will post separate question on this.

My question here is this: Can now (version 9) tell sagemath to set a timeout on some call and have sagemath issue an error (may be exception) if timeout expires and the call have not completed yet? I am mainly interested in integrate calls, which some take long time.

Here is an example of how this is done in Maple limits the amount of CPU time spent on a computation

restart; 
integrand:=(b*x + a)^(3/2)*(d*x + c)^(5/2)/x^7;
try
    timelimit(300,int(integrand,x));
    print("Finished before time out, good");
catch:
    print("opps, timed out");
end try;

Is it possible to do the above directly in sagemath without me having to program the timelimit myself using Process and Queues? I am using sagemath 9 on Linux.

can one now set a timelimit on operation in sagemath?

I have found serious bug related to my own way of doing timeout when using sagemath on some integrals. I think it is a bug in sagemath. Will post separate question on this.this after this one.

My question here is this: Can now (version 9) tell sagemath to set a timeout on some call and have sagemath issue an error (may be exception) if timeout expires and the call have not completed yet? I am mainly interested in integrate calls, which some take long time.

Here is an example of how this is done in Maple limits the amount of CPU time spent on a computation

restart; 
integrand:=(b*x + a)^(3/2)*(d*x + c)^(5/2)/x^7;
try
    timelimit(300,int(integrand,x));
    print("Finished before time out, good");
catch:
    print("opps, timed out");
end try;

Is it possible to do the above directly in sagemath without me having to program the timelimit myself using Process and Queues? I am using sagemath 9 on Linux.

can one now set a timelimit on operation in sagemath?

I have found serious bug related to my own way of doing timeout when using sagemath on some integrals. I think it is a bug in sagemath. Will post separate question on this after this one.

My question here is this: Can now (version 9) tell sagemath to set a timeout on some call and have sagemath issue an error (may be exception) if timeout expires and the call have not completed yet? I am mainly interested in integrate calls, which some take long time.

Here is an example of how this is done in Maple limits the amount of CPU time spent on a computation

restart; 
integrand:=(b*x + a)^(3/2)*(d*x + c)^(5/2)/x^7;
try
    timelimit(300,int(integrand,x));
    print("Finished before time out, good");
catch:
    print("opps, timed out");
end try;

Is it possible to do the above directly in sagemath without me having to program the timelimit myself using Process and Queues? I am using sagemath 9 on Linux.

can one now set a timelimit on operation in sagemath?

My question here is this: Can now (version 9) tell sagemath to set a timeout on some call and have sagemath issue an error (may be exception) if timeout expires and the call have not completed yet? I am mainly interested in integrate calls, which some take long time.

Here is an example of how this is done in Maple limits the amount of CPU time spent on a computation

restart; 
integrand:=(b*x + a)^(3/2)*(d*x + c)^(5/2)/x^7;
try
    timelimit(300,int(integrand,x));
    print("Finished before time out, good");
catch:
    print("opps, timed out");
end try;

Is it possible to do the above directly in sagemath without me having to program the timelimit myself using Process and Queues? I am using sagemath 9 on Linux.

update

I am getting stack dump when implemented the alaram method. I am not sure why that is. This happens in few cases. Below is a MWE to reproduce it.

I created a file build_fricas_new_timeout_one_integral.sage with content

#!/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:      
    print("Timed out")
else:
    print("Completed OK, anti=",anti)
    cancel_alarm()

can one now set a timelimit on operation in sagemath?

My question here is this: Can now (version 9) tell sagemath to set a timeout on some call and have sagemath issue an error (may be exception) if timeout expires and the call have not completed yet? I am mainly interested in integrate calls, which some take long time.

Here is an example of how this is done in Maple limits the amount of CPU time spent on a computation

restart; 
integrand:=(b*x + a)^(3/2)*(d*x + c)^(5/2)/x^7;
try
    timelimit(300,int(integrand,x));
    print("Finished before time out, good");
catch:
    print("opps, timed out");
end try;

Is it possible to do the above directly in sagemath without me having to program the timelimit myself using Process and Queues? I am using sagemath 9 on Linux.

update

I am getting stack dump when implemented the alaram method. I am not sure why that is. This happens in few cases. Below is a MWE to reproduce it.

I created a file build_fricas_new_timeout_one_integral.sage with content

#!/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:      
    print("Timed out")
else:
    print("Completed OK, anti=",anti)
    cancel_alarm()

Then called it as follows sage ./build_fricas_new_timeout_one_integral.sage then I get this on the screen

>sage ./build_fricas_new_timeout_one_integral.sage 
Interrupting FriCAS...
Traceback (most recent call last):
  File "/usr/lib/python3.8/site-packages/sage/interfaces/expect.py", line 986, in _eval_line
    E.expect(self._prompt)
  File "/usr/lib/python3.8/site-packages/pexpect/spawnbase.py", line 343, in expect
    return self.expect_list(compiled_pattern_list,
  File "/usr/lib/python3.8/site-packages/pexpect/spawnbase.py", line 372, in expect_list
    return exp.expect_loop(timeout)
  File "/usr/lib/python3.8/site-packages/pexpect/expect.py", line 169, in expect_loop
    incoming = spawn.read_nonblocking(spawn.maxread, timeout)
  File "/usr/lib/python3.8/site-packages/pexpect/pty_spawn.py", line 500, in read_nonblocking
    if (timeout != 0) and select(timeout):
  File "/usr/lib/python3.8/site-packages/pexpect/pty_spawn.py", line 450, in select
    return select_ignore_interrupts([self.child_fd], [], [], timeout)[0]
  File "/usr/lib/python3.8/site-packages/pexpect/utils.py", line 143, in select_ignore_interrupts
    return select.select(iwtd, owtd, ewtd, timeout)
  File "src/cysignals/signals.pyx", line 320, in cysignals.signals.python_check_interrupt
cysignals.signals.AlarmInterrupt

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "./build_fricas_new_timeout_one_integral.sage.py", line 22, in <module>
    anti = doTheIntegration()        
  File "./build_fricas_new_timeout_one_integral.sage.py", line 17, in doTheIntegration
    anti=integrate(integrand,x,algorithm="fricas")                        
  File "/usr/lib/python3.8/site-packages/sage/misc/functional.py", line 753, in integral
    return x.integral(*args, **kwds)
  File "sage/symbolic/expression.pyx", line 12391, in sage.symbolic.expression.Expression.integral (build/cythonized/sage/symbolic/expression.cpp:64575)
  File "/usr/lib/python3.8/site-packages/sage/symbolic/integration/integral.py", line 927, in integrate
    return integrator(expression, v, a, b)
  File "/usr/lib/python3.8/site-packages/sage/symbolic/integration/external.py", line 386, in fricas_integrator
    result = ex.integrate(v)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/interface.py", line 680, in __call__
    return self._obj.parent().function_call(self._name, [self._obj] + list(args), kwds)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/interface.py", line 601, in function_call
    return self.new(s)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/interface.py", line 370, in new
    return self(code)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/interface.py", line 296, in __call__
    return cls(self, x, name=name)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/expect.py", line 1471, in __init__
    self._name = parent._create(value, name=name)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/interface.py", line 501, in _create
    self.set(name, value)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/fricas.py", line 589, in set
    output = self.eval(cmd, reformat=False)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/fricas.py", line 847, in eval
    output = Expect.eval(self, code, strip=strip,
  File "/usr/lib/python3.8/site-packages/sage/interfaces/expect.py", line 1384, in eval
    return '\n'.join([self._eval_line(L, allow_use_file=allow_use_file, **kwds)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/expect.py", line 1384, in <listcomp>
    return '\n'.join([self._eval_line(L, allow_use_file=allow_use_file, **kwds)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/expect.py", line 1017, in _eval_line
    self._keyboard_interrupt()
  File "/usr/lib/python3.8/site-packages/sage/interfaces/expect.py", line 1039, in _keyboard_interrupt
    raise KeyboardInterrupt("Ctrl-c pressed while running %s" % self)
KeyboardInterrupt: Ctrl-c pressed while running FriCAS
>

Am I doing something wrong in using the alarm method?

can one now set a timelimit on operation in sagemath?

My question here is this: Can now (version 9) tell sagemath to set a timeout on some call and have sagemath issue an error (may be exception) if timeout expires and the call have not completed yet? I am mainly interested in integrate calls, which some take long time.

Here is an example of how this is done in Maple limits the amount of CPU time spent on a computation

restart; 
integrand:=(b*x + a)^(3/2)*(d*x + c)^(5/2)/x^7;
try
    timelimit(300,int(integrand,x));
    print("Finished before time out, good");
catch:
    print("opps, timed out");
end try;

Is it possible to do the above directly in sagemath without me having to program the timelimit myself using Process and Queues? I am using sagemath 9 on Linux.

update

I am getting stack dump when implemented implementing the alaram method. alarm method shown in the answer below. I am not sure why that is. This happens in few cases. May be I am making an error somewhere. Below is a MWE to reproduce it.

I created a file build_fricas_new_timeout_one_integral.sage with content

#!/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:      
    print("Timed out")
else:
    print("Completed OK, anti=",anti)
    cancel_alarm()

Then called it as follows sage ./build_fricas_new_timeout_one_integral.sage then I get this on the screen

>sage ./build_fricas_new_timeout_one_integral.sage 
Interrupting FriCAS...
Traceback (most recent call last):
  File "/usr/lib/python3.8/site-packages/sage/interfaces/expect.py", line 986, in _eval_line
    E.expect(self._prompt)
  File "/usr/lib/python3.8/site-packages/pexpect/spawnbase.py", line 343, in expect
    return self.expect_list(compiled_pattern_list,
  File "/usr/lib/python3.8/site-packages/pexpect/spawnbase.py", line 372, in expect_list
    return exp.expect_loop(timeout)
  File "/usr/lib/python3.8/site-packages/pexpect/expect.py", line 169, in expect_loop
    incoming = spawn.read_nonblocking(spawn.maxread, timeout)
  File "/usr/lib/python3.8/site-packages/pexpect/pty_spawn.py", line 500, in read_nonblocking
    if (timeout != 0) and select(timeout):
  File "/usr/lib/python3.8/site-packages/pexpect/pty_spawn.py", line 450, in select
    return select_ignore_interrupts([self.child_fd], [], [], timeout)[0]
  File "/usr/lib/python3.8/site-packages/pexpect/utils.py", line 143, in select_ignore_interrupts
    return select.select(iwtd, owtd, ewtd, timeout)
  File "src/cysignals/signals.pyx", line 320, in cysignals.signals.python_check_interrupt
cysignals.signals.AlarmInterrupt

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "./build_fricas_new_timeout_one_integral.sage.py", line 22, in <module>
    anti = doTheIntegration()        
  File "./build_fricas_new_timeout_one_integral.sage.py", line 17, in doTheIntegration
    anti=integrate(integrand,x,algorithm="fricas")                        
  File "/usr/lib/python3.8/site-packages/sage/misc/functional.py", line 753, in integral
    return x.integral(*args, **kwds)
  File "sage/symbolic/expression.pyx", line 12391, in sage.symbolic.expression.Expression.integral (build/cythonized/sage/symbolic/expression.cpp:64575)
  File "/usr/lib/python3.8/site-packages/sage/symbolic/integration/integral.py", line 927, in integrate
    return integrator(expression, v, a, b)
  File "/usr/lib/python3.8/site-packages/sage/symbolic/integration/external.py", line 386, in fricas_integrator
    result = ex.integrate(v)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/interface.py", line 680, in __call__
    return self._obj.parent().function_call(self._name, [self._obj] + list(args), kwds)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/interface.py", line 601, in function_call
    return self.new(s)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/interface.py", line 370, in new
    return self(code)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/interface.py", line 296, in __call__
    return cls(self, x, name=name)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/expect.py", line 1471, in __init__
    self._name = parent._create(value, name=name)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/interface.py", line 501, in _create
    self.set(name, value)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/fricas.py", line 589, in set
    output = self.eval(cmd, reformat=False)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/fricas.py", line 847, in eval
    output = Expect.eval(self, code, strip=strip,
  File "/usr/lib/python3.8/site-packages/sage/interfaces/expect.py", line 1384, in eval
    return '\n'.join([self._eval_line(L, allow_use_file=allow_use_file, **kwds)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/expect.py", line 1384, in <listcomp>
    return '\n'.join([self._eval_line(L, allow_use_file=allow_use_file, **kwds)
  File "/usr/lib/python3.8/site-packages/sage/interfaces/expect.py", line 1017, in _eval_line
    self._keyboard_interrupt()
  File "/usr/lib/python3.8/site-packages/sage/interfaces/expect.py", line 1039, in _keyboard_interrupt
    raise KeyboardInterrupt("Ctrl-c pressed while running %s" % self)
KeyboardInterrupt: Ctrl-c pressed while running FriCAS
>

Am I doing something wrong in using the alarm method?

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