hese sizes are fixed when the function is called
and the container is instantiated. Also, declarations may be inside
loops and thus may change over the course of running a program, but
each time a declaration is visited, it declares a fixed size object.</p>
<p>When an index is provided that is out of bounds, Stan throws a
rejection error and computation on the current log density and
gradient evaluation is halted and the algorithm is left to clean up
the error. All of Stan’s containers check the sizes of 