hlight"><pre>sqrt( sum( square( x ) ) ) &lt;= 1
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<p>is convex, but it violates the ruleset&#8212;so it is rejected. However, the
mathematically equivalent form</p>
<div class="highlight-none"><div class="highlight"><pre>norm( x ) &lt;= 1
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<p>is acceptable.
If your error is of this type, you will need to find a way to express your
problem in a DCP-compliant manner. We have attempted to supply all of the commonly used
functions that the underlying solvers can support; so 