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+====== Complex Matrix class ======
+As of Auryn v0.8 the library comes with a complex matrix class which generalizes [[SimpleMatrix]] to synaptic connections which can have more than just a single scalar value per connection. [[ComplexMatrix]] is essentially a rank three tensor class optimized for sparse synaptic transmission.
+More specifically, like SimpleMatrix the complex matrix class implements a sparse matrix that allows fast access of all elements of one row. It provides row iterators to efficiently propagate
+spikes. Memory has to be reserved when the class is defined and elements can
+only be inserted row by row starting from "top left to bottom right". This scheme enables
+related data fields to reside in memory next to each other.
+ComplexMatrix generalizes SimpleMatrix to a rank 3 tensor in which each
+synaptic connection can have more than one value (third tensor mode --
+corresponding to a synaptic state). This allows to efficiently implement state
+based complex synaptic models which have their own internal dynamics.
+Instead of storing all synaptic data values in one long array the synaptic
+state values are stored in multiple state vectors which can be manipulated
+efficiently in a vector based manner.
+For instance, suppose ''w'' holds your instance of ComplexMatris in which you have
+''set_num_synapse_states(3)''. This makes it a connectivity matrix which reserves
+three state variables of type AurynWeight per synaptic connection.
+Now, decaying all elements of, say, state 3 by a factor ''foo'' is as simple as
+''w->get_state_vector(2)->scale(foo)''.
+Adding two of the states for all synapses
+becomes
+<code>
+w->get_state_vector(2)->add(w->get_state_vector(3))
+</code>
+As you imagine these expressions can quickly become rather lengthy.
+It is therefore nice to declare shortcuts in your plastic Connection class such as:
+<code>
+AurynSynStateVector * w_val        = w->get_state_vector(0);
+AurynSynStateVector * tagging_val  = w->get_state_vector(1);
+AurynSynStateVector * scaffold_val = w->get_state_vector(2);
+</code>
+You can now work with these as you are used with AurynVector or
+AurynStateVector instances ''w_val->saxpy(foo,tagging_val)''