You can't solve problem 1 using either optimset or optimoptions.
The Optimization Toolbox options reference page shows that UseParallel is not used by quadprog. optimset will return a struct array with that field present, and you can change that field if you like, but quadprog doesn't do anything with that field if you pass that options structure into it. As one check of this, the word "parallel" does not appear at all on the quadprogdocumentation page.
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