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copied!<p>It depends very much on <strong>what kind of operations</strong> you are going to perform on that structure. Will you have to do <em>searches</em>? If so, what kind: value-based or position-based? Will you have to perform <em>transformations</em> on it? Will you have to access all of its elements repeatedly and in a sequence? Will you have to access elements based on their <em>position</em> in the grid? Is your structure <em>sparse</em> or <em>dense</em>?</p> <p>Moreover, do you want to minimize <em>creation</em> time, <em>search</em> time, <em>navigation</em> time, or <em>transformation</em> time? This all gives fundamental information to make a decision.</p> <p>I would <strong>not</strong> go for a solution based on nodes and links, because it is:</p> <ol> <li>expensive in terms of <em>memory consumption</em> (due to the extra link pointers);</li> <li>expensive in terms of <em>complexity</em> (navigating all the nodes require following all the links, so no random access), and;</li> <li>expensive in terms of <em>data locality</em> (nodes will be allocated individually and spread all over the heap at separate addresses, which will generate many cache misses and slow down your program);</li> <li><em>error-prone</em> (messing up with links is easy, especially if you use raw pointers and don't want to pay for smart pointers' memory overhead)</li> </ol> <p>Without knowing too much about your requirements, I would probably suggest you having a look at <a href="http://www.boost.org/doc/libs/1_52_0/libs/multi_array/doc/user.html" rel="noreferrer">Boost.MultiArray</a>.</p> <p>If you want to do things on your own, then (again, without knowing too much about your requirements) I would suggest you using a <code>vector<vector<vector<double>>></code>, which is relatively simple, does not have fixed size and allows you resizing at run-time, guarantees you O(1) access through the subscripting operator and also <em>some</em> locality of the data (you have several vectors here, so as long as you access data from <em>one</em> vector performance will be fine).</p> <p>A plain C-style multi-dimensional array is also a possibility, but it's inherently unsafe, which would make it a last-resort choice if I were you (also, allocating a contiguous block of memory might be impossible if your structure is huge).</p>

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