The successful application of the real-coded differential evolution (DE) to a wide range of real-valued problems has motivated researchers to investigate its potentiality to integer and discrete valued problems. In most of such works, a real-valued solution is converted into a desired integer-valued solution by applying some posterior decoding mechanisms. Only a limited number of works are found, in which attempts are made for developing an actual integer-coded DE. In this article, such a DE is presented which can work directly with real, integer and discrete variables of a problem without any conversion. In the computational experiments carried out with a set of test problems taken from literature, the DE improved several previously known best solutions, as well as outperformed some similar proposals in most of the cases. 
A real–integer–discrete-coded differential evolution