[Cbc] Using SOS1 getting malloc: pointer being freed was not allocated

[John Forrest]

Ryan,

a) still bug with depth - will find and fix.
b) I don't read the ?documentation? - if you do cbc and then depth?? you 
will see that with no depth set the problem is thought to be too big (> 
500 variables).  It says to switch off then use depth -999.

So my advice to set depth -100 was bad - it tried the small B&B at a 
depth >200 - should be able to find bug.

John
On 02/01/18 13:59, Rhavar wrote:
> I think you're right. There is probably some bugs in my code causing 
> the models to be slightly different.
>
> But try this:  `cbc no-SOS.lp solve solution $`
>
> Result - Optimal solution found
>
> Objective value:81001582.00000000
>
>
> But trying with `cbc no-SOS.lp depth -100 solve solution $`
>
> Result - Optimal solution found
>
> Objective value:81009832.00000000
>
>
> Giving a worse solution. I wonder if that's related to the previous 
> bug you fixed?
>
>
> -Ryan
>
>
>> -------- Original Message --------
>> Subject: Re: [Cbc] Using SOS1 getting malloc: pointer being freed was 
>> not allocated
>> Local Time: January 2, 2018 6:02 AM
>> UTC Time: January 2, 2018 12:02 PM
>> From: john.forrest at fastercoin.com
>> To: Rhavar <rhavar at protonmail.com>
>> cbc at list.coin-or.org <cbc at list.coin-or.org>
>>
>>
>> Ryan,
>>
>> Are you sure they are the same?
>>
>> I get 80985022 using with-SOS (no_change 1) and 81001582 using 
>> no-SOS.  If they are equivalent then fixing has_change to 0 in no-SOS 
>> should be same as fixing no_change to 1 in with-SOS - but the two LP 
>> relaxations have different objective values.
>>
>> John
>> On 01/01/18 19:06, Rhavar wrote:
>>> Sorry, I got that in reverse.
>>>
>>> https://gist.github.com/RHavar/35479c3f6d7f91963b089615859543a6
>>>
>>> The two problems should logically be equivalent to each other, 
>>> however the one with SOS gives a better optimal than the one without.
>>>
>>>
>>>
>>> -Ryan
>>>
>>>
>

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