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    <p>I do the following (array type is container/iterator range concept):</p> <pre><code>ublas::matrix&lt;douple&gt; A; foreach (double &amp; element, A.data()) { } </code></pre> <p>However, this will not work for slices: your best solution is to write an iterator for them.</p> <p>Here is an example of using <code>multi_array</code> to provide storage of a custom class. Perhaps you could do the same:</p> <pre><code>template&lt;size_t N, typename T&gt; struct tensor_array : boost::multi_array_ref&lt;T,N&gt; { typedef boost::multi_array_ref&lt;T,N&gt; base_type; typedef T value_type; typedef T&amp; reference; typedef const T&amp; const_reference; tensor_array() : base_type(NULL, extents()) { // std::cout &lt;&lt; "create" &lt;&lt; std::endl; } template&lt;class A&gt; tensor_array(const A &amp;dims) : base_type(NULL, extents()) { //std::cout &lt;&lt; "create" &lt;&lt; std::endl; resize(dims); } template&lt;typename U&gt; void resize(const U (&amp;dims)[N]) { boost::array&lt;U,N&gt; dims_; std::copy(dims, dims + N, dims_.begin()); resize(dims_); } template&lt;typename U&gt; void resize(const boost::array&lt;U,N&gt; &amp;dims) { size_t size = 1; boost::array&lt;size_t,N&gt; shape; for (size_t i = 0; i &lt; N; ++i) { size *= dims[i]; shape[N-(i+1)] = dims[i]; } data_.clear(); data_.resize(size, 0); // update base_type parent set_base_ptr(&amp;data_[0]); this-&gt;num_elements_ = size; reshape(shape); } size_t size() const { return data_.size(); } size_t size(size_t i) const { return this-&gt;shape()[N-(i+1)]; } tensor_array&amp; fill(const T &amp;value) { std::fill(data_.begin(), data_.end(), value); return *this; } private: typedef boost::detail::multi_array::extent_gen&lt;N&gt; extents; std::vector&lt;T&gt; data_; }; </code></pre>
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    1. COYeah, I know. I mean like the whole idea seems wrong to me - to use `ublas::matrix` as a plain 2d container for elements. That's why I'm looking for something similiar and with the same functionality in terms of iterating / subranging.
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    2. CO@Hard maybe you could hide matrix inside custom class and control what features you expose? although, I see nothing wrong with using matrix just a storage.
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