Or-tools: Exception thrown while calling SetRange method.

[tigrandp]

I wanted to solve vehicle routing problem instance as a usage example I used cvrptw.py. Then I have created weekly model which has time_horizon=5x24x3600(the total number of seconds in a week). After that when I setting time constraints :
time_dimension.CumulVar(int(customer.index)).SetRange( customer.tw_open, customer.tw_close)

I am getting exception like this :
ortools-2.3393-py2.7-linux-x86_64.egg/ortools/constraint_solver/pywrapcp.py", line 1300, in SetRange return _pywrapcp.IntExpr_SetRange(self, l, u) Exception: CP Solver fail

In that case tw_open=28800 and tw_close=68400. I expected to get more informative exception message to be able to understand what I am doing wrong.

[furnon]

What's the value of time_dimension.CumulVar(int(customer.index)).GetMin()
and GetMax() just before the call to SetRange ?

On Wed, Mar 16, 2016 at 11:35 AM, Tigran Hakobyan [email protected]
wrote:

I wanted to solve vehicle routing problem instance as a usage example I
used cvrptw.py. Then I have created weekly model which has time_horizon=5
_24_3600(the total number of seconds in a week). After that when I
setting time constraints :
time_dimension.CumulVar(int(customer.index)).SetRange(
customer.tw_open,
customer.tw_close)

I am getting exception like this :
ortools-2.3393-py2.7-linux-x86_64.egg/ortools/constraint_solver/pywrapcp.py",
line 1300, in SetRange
return _pywrapcp.IntExpr_SetRange(self, l, u)
Exception: CP Solver fail

In that case tw_open=28800 and tw_close=68400. I expected to get more
informative exception message to be able to understand what I am doing
wrong.

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[tigrandp]

Here is what I got :

print ('Min=', time_dimension.CumulVar(int(stop.index)).GetMin())
  File "/lib/python2.7/site-packages/ortools-2.3393-py2.7-linux-x86_64.egg/ortools/constraint_solver/pywrapcp.py", line 1436, in <lambda>
    __getattr__ = lambda self, name: _swig_getattr(self, IntVar, name)
  File "/lib/python2.7/site-packages/ortools-2.3393-py2.7-linux-x86_64.egg/ortools/constraint_solver/pywrapcp.py", line 74, in _swig_getattr
    return _swig_getattr_nondynamic(self, class_type, name, 0)
  File "/lib/python2.7/site-packages/ortools-2.3393-py2.7-linux-x86_64.egg/ortools/constraint_solver/pywrapcp.py", line 69, in _swig_getattr_nondynamic
    return object.__getattr__(self, name)
AttributeError: type object 'object' has no attribute '__getattr__'

[tigrandp]

Sorry for incovenience, it seems something wrong on my side, cause I changed cvrptw.py to use the same time frames and it worked smoothly.

[alanbato]

@tigrandp What was your mistake? I'm having the same issue right now and I'm doing something similar to your week-period horizon

[tigrandp]

@Alanbato please paste error here or code I will try to help I do not remember.

[alanbato]

@tigrandp Hello, thank you for your fast reply

Here's the error I'm getting when trying to solve my problem:

<ipython-input-25-7418aa8aeead> in <module>()
    190 
    191 if __name__ == '__main__':
--> 192     main()

<ipython-input-25-7418aa8aeead> in main()
     87             time_dimension.CumulVar(int(cust.index)).SetRange(
     88                 int(cust.tw_open.total_seconds()),
---> 89                 int(cust.tw_close.total_seconds()))
     90 
     91     """

~/lib/python2.7/site-packages/ortools-4.2.3790-py2.7-linux-x86_64.egg/ortools/constraint_solver/pywrapcp.pyc in SetRange(self, l, u)
   1337 
   1338     def SetRange(self, l, u):
-> 1339         return _pywrapcp.IntExpr_SetRange(self, l, u)
   1340 
   1341     def SetValue(self, v):

Exception: CP Solver fail

[tigrandp]

try to check :

time_dimension.CumulVar(int(cust.index)).Max() >= time_dimension.CumulVar(int(cust.index)).Min()

and then

cust.index < routing.nodes()

[alanbato]

Both of them are True :sweat:

[paraCRM]

And I have the same mistake.
I need to solve the problem with total time constraint. I know, that this is solving by time_horizon in AddDimension.
But my nodes have over day time windows, for example it open at 23:00 and close at 01:00 next day.
So I convert it to 82800 and 90000.
But total time constraint is only 12 hours, 43200.
So I want open depot from 0 to 259200 (not to 43200, thats how AddDimension works) and add 1 day to all customers, so that this customer will be 169200 and 176400.
In this case i understand, that dimension of time_horizon have to be equal as max dimension of time windows.
For example, if my max time windows dimension (on customers, not on depot) will be = 176400 (6 characters) time_horizon 43200 (5 characters) will raise an error

Traceback (most recent call last):
File "D:/Work/VRPTW/VRPTW3/cvrptw.py", line 342, in
main()
File "D:/Work/VRPTW/VRPTW3/cvrptw.py", line 235, in main
time_dimension.CumulVar(locations).SetRange(start, end)
File "C:\Users\MDesh.virtualenvs\VRPTW3-rmdLUytm\lib\site-packages\ortools\constraint_solver\pywrapcp.py", line 1339, in SetRange
return _pywrapcp.IntExpr_SetRange(self, l, u)
Exception: CP Solver fail

But if time_horizon will be , for example, 143200 (6 characters) - everything will be ok.
So that there are two ways - to open the depot for my task (i dont know, how i can do it, i ll ask about it in the new issue, #533) and, probably, repair this error.
Will be grateful for any help.
Thanks.

[tatadyj]

Hi Guys, I have the same problem and issues when I implemented my model.
Please check If you set fix_start_cumul_to_zero == false, whether the problem will be solved.
We need to set this value to FALSE, if we do not want to cumulate from zero, which is the lower bound.

[lperron]

Are you calling set range outside search?
This is not supported.

You should add a constraint instead of calling a modifier.
Laurent Perron | Operations Research | [email protected] | (33) 1 42 68 53
00

Le mar. 15 mai 2018 à 17:00, Yajun Ding [e-mail] a écrit :

Hi Guys, I have the same problem and issues when I implemented my model.
Please check If you set fix_start_cumul_to_zero == false, whether the
problem will be solved.
We need to set this value to FALSE, if we do not want to cumulate from
zero, which is the lower bound.

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[subasgiri]

Hi Guys i am also facing the similar issue.
i am running the below code but getting some issue. Please help me finding out the issue.

Code:

time_dimension.CumulVar(index).SetRange(location_time_window[0], location_time_window[1])

Error:

TypeError                                 Traceback (most recent call last)
<ipython-input-1-fb312911ee19> in <module>
    158 
    159 if __name__ == '__main__':
--> 160   main()

<ipython-input-1-fb312911ee19> in main()
    147   # Add Time Window constraint
    148   time_callback = create_time_callback(data)
--> 149   add_time_window_constraints(routing, data, time_callback)
    150   # Setting first solution heuristic (cheapest addition).
    151   search_parameters = pywrapcp.RoutingModel.DefaultSearchParameters()

<ipython-input-1-fb312911ee19> in add_time_window_constraints(routing, data, time_callback)
     88         print(location_time_window[1].item())
     89         #print("=============================================")
---> 90         time_dimension.CumulVar(index).SetRange(location_time_window[0], location_time_window[1])
     91 
     92         print(type(location_time_window[0]))

~\AppData\Roaming\Python\Python37\site-packages\ortools\constraint_solver\pywrapcp.py in SetRange(self, l, u)
   1340 
   1341     def SetRange(self, l: 'int64', u: 'int64') -> "void":
-> 1342         return _pywrapcp.IntExpr_SetRange(self, l, u)
   1343 
   1344     def SetValue(self, v: 'int64') -> "void":

TypeError: in method 'IntExpr_SetRange', argument 2 of type 'int64'

[alanbato]

As @lperron said, you might want to try adding constraints instead of setting the range, like this:

solver.Add(time_dimension.CumulVar(index) >= location_time_window[0])
solver.Add(time_dimension.CumulVar(index) <= location_time_window[1])

or, if you don't want to use constraints for some reason, try setting the min and max values independently.

time_dimension.CumulVar(index).SetMin(location_time_window[0])
time_dimension.CumulVar(index).SetMax(location_time_window[1])

Sometimes I fix errors that mention argument 2 of type 'int64' by doing an explicit cast to int, but I don't know why this works.

Hope it helps.

[vkarpov15]

I ran into this issue recently, turns out I had fix_start_cumul_to_zero set to true, and you get this error if you try to SetMin() to a positive value with fix_start_cumul_to_zero = True.

[Mizux]

@vkarpov15 did you try to setMin() on a vehicle start node or a "location to visit" node ?

[akarsh1995]

let's say vehicle starts 9.00 AM (3600x9 = 32400)
if you're setting dimension with fix_start_cumul_to_zero=False

your capacity argument while setting dimension should be greater than 32400

routing.AddDimension(... , capacity>32400)

[ymiladi]

let's say vehicle starts 9.00 AM (3600x9 = 32400)
if you're setting dimension with fix_start_cumul_to_zero=False

your capacity argument while setting dimension should be greater than 32400

routing.AddDimension(... , capacity>32400)

I had the same problem and found out that I'm missing my waiting total vehicle max time by a digit :)))