A method and apparatus for direct mapping in a compute unit having an internal random access memory the primary operational sequences of an algorithm to related function including storing in an internal random access memory at least one predetermined direct mapped function value for each primary operational sequence of an algorithm; holding in an input data register the address in the random access memory of at least one mapped function value for a selected primary operational sequence of the algorithm and holding in an output register the at least one mapped function value for the selected primary operational sequence of the algorithm read out of the random access memory.