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    <p>You don't need to use static function directly. Instead you can write a very general wrapper.</p> <p><a href="https://stackoverflow.com/questions/13074756/how-to-avoid-static-member-function-when-using-gsl-with-c">I believe this is a duplicate question</a>. <a href="https://stackoverflow.com/a/18181494/2472169">My answer</a> to the question I just linked is based on the wrapper presented <a href="https://stackoverflow.com/questions/10593726/a-function-pointer-issue-how-to-efficiently-interface-with-c-api-ie-gsl-from">here</a>. However, I generalized it using templates to avoid the <a href="https://stackoverflow.com/questions/14677997/stdfunction-vs-template/15015502#15015502">performance penalty of std::function</a> due to heap allocation of the functor that std::function holds (the original answer only warns the reader about the penalty that is caused by the multiple indirection involved in std::function implementation, and this is negligible in comparison to the problem caused by heap allocation).</p> <p>EDIT 1: This issue is also discussed <a href="https://stackoverflow.com/questions/13289311/c-function-pointers-with-c11-lambdas">here</a> </p> <p>EDIT 2 (to answer a question you raised in your first comment to my answer). The first caveat is that you have to make sure that whatever <code>std::function</code> holds is not deleted before GSL finish the calculation. Also, @Managu pointed out that the wrapper itself must not be out of scope while GSL works. This is not hard to enforce if you code carefully. Example of bad code:</p> <pre><code> // BAD PROGRAM - EXAMPLE OF WHAT YOU MUST NOT DO. DO NOT COPY THIS CODE // HERE THE WRAPPER GETS PREMATURELY OUT OF SCOPE =&gt; CRASH gsl_function *F auto ptr = [](double x)-&gt;double{return 2*x;}; std::function&lt;double(double)&gt; FF1(std::cref(ptr)) { gsl_function_pp Fp(FF1); F = static_cast&lt;gsl_function*&gt;(&amp;Fp); } (...) // CALL GSL </code></pre>
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    1. COThanks for the guidance. Are there any caveats that I should be aware of, especially since I want to call on these functions multiple times for each element of an array of ODE objects? @Managu mentioned [here](http://stackoverflow.com/questions/10593726/a-function-pointer-issue-how-to-efficiently-interface-with-c-api-ie-gsl-from) doing something along those lines is not advised.
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    2. COHope EDIT2 helps to answer your concern
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