[Cbc] Problem with Cbc trunk

[John Forrest]

This only just appeared in my inbox - although dated 15/10/12

If just the name of a file is given to cbc then an implicit -solve is 
added.  What you want is

./cbc p0201.mps -solve -solution $


On 15/10/12 20:17, Horand Gassmann wrote:
> Hi,
>
> I have a very strange situation trying to run some tests with Cbc. My 
> test problem, p0201.mps solves fine, as long as I do not supply any 
> user options. As soon as I add another character to the command line, 
> Cbc returns a suboptimal solution, which it obtains without a single 
> iteration. I must be missing something obvious, but I have spent all 
> afternoon trying to figure it out.
>
> Any ideas?
>
> Thanks
>
> gus
>
>
> $ ./cbc p0201.mps
>
> ...
>
> Result - Optimal solution found
>
> Objective value:                7615.00000000
> Enumerated nodes:               34
> Total iterations:               6184
> Time (CPU seconds):             6.24
> Time (Wallclock seconds):       6.32
>
> Total time (CPU seconds):       6.24   (Wallclock seconds): 6.33
>
> $ ./cbc p0201.mps -solution stdout
> Welcome to the CBC MILP Solver
> Version: Trunk (unstable)
> Build Date: Oct 14 2012
> Revision Number: 1793
>
> command line - ./cbc p0201.mps -solution stdout (default strategy 1)
> At line 15 NAME          P0201
> At line 16 ROWS
> At line 151 COLUMNS
> At line 1270 RHS
> At line 1311 BOUNDS
> At line 1513 ENDATA
> Problem P0201 has 133 rows, 201 columns and 1923 elements
> Coin0008I P0201 read with 0 errors
> Status unknown - objective value 0.00000000
> Total time (CPU seconds):       0.00   (Wallclock seconds): 0.00
>
> $
>
>
> -------------------------------------------------------
>
> Horand I. Gassmann, Professor
>
> Kenneth C. Rowe School of Business, Dalhousie University
> 6100 University Avenue, PO Box 15000
> Halifax, Nova Scotia, Canada, B3H 4R2
> ph. (902) 494-1844
> fax (902) 494-1107
>
> http://myweb.dal.ca/gassmann/
>
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