1. A computer-readable medium containing instructions executable by at least one processor, the computer-readable medium comprising: one or more instructions for providing an interface to permit a user to build or edit a graphical model that includes at least one block and a plurality of connections, each of the plurality of connections representing a signal received by or output from the at least one block; one or more instructions for receiving information regarding one of the signals, in the graphical model, that has a size or dimensionality that can change during execution of the graphical model; one or more instructions for visually presenting the graphical model, where a single one of the plurality of connections corresponding to the one signal implicitly conveys the size or the dimensionality of the one signal that can change during execution of the graphical model; and one or more instructions for generating code from the graphical model.