1. A non-transitory, computer readable memory medium comprising program instructions for creating a graphical program, wherein the program instructions are executable to: display a function block in a graphical program, wherein the function block is configured to perform a first function, wherein the function block comprises one or more inputs and one or more outputs, and wherein the graphical program comprises a first plurality of interconnected blocks which visually indicate the functionality of the graphical program; receive user input selecting the function block to configure the function block; receive user input assembling a second graphical program that visually specifies calculation of attributes of the one or more outputs based on attributes of the one or more inputs, wherein the second graphical program comprises a second plurality of interconnected blocks which visually indicate the calculation of the attributes of the one or more outputs, wherein said receiving user input assembling is performed in response to the user input selecting the function block.