How is this site ranked relative to other sites? We’re always looking to partner with companies who offer investing tools like apps, trading tools, or websites with subscription content. Please contact us with any business development opportunities at firstname.lastname@example.org. For four variables, the K-map is specially convenient, since it can be drawn in a simple form, and the problems can be complex enough for the method to be valuable. The case of three variables is intermediate; K-maps are easily drawn and used, but the problems are not very difficult. K-maps can also be drawn for five or six variables, but are a bit like Mr Spock's multidimensional chess game and less than easy to visualize. In every case, however, the principles are the same. For more variables than four or possibly five, computer methods of simplification (minimization) are useful and rather powerful. However, the profitablility of such analyses is doubtful, and are applicable to problems that are no longer of much importance, since complex logic is no longer constructed from discrete gates. Walmart is going after Amazon on one of its signature offerings — and undercutting the price.