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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>There is an irritating, but avoidable problem with fixing
variables in SOS of type 2. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I’ve been finding it useful to fix the variables in
SOS which are satisfied at the continuous optimum - in the S1 case by setting
the lower bound on the non-zero variable to 1.0 and/or the upper bounds on the
zero variables to zero. It turns out that if you set the lower bound on a S2
set variable to 1.0 Cbc throws an exception. However, if you just set
upper bounds to zero it works OK.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>--John<o:p></o:p></span></font></p>
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