“First make it work, then make it faster” — Brian Kerningham
However, if the program takes too long to run, it might not be possible to make it correct. Iterative development breaks down when each iteration takes several hours. Some R code I was working with was supposed to run for a 1000 iterations, but with each iteration taking 75 seconds to run, we couldn’t take the time to let it run to completion. The problem was the continued appending of rows to a data.frame object. Referred to as the Second Circle here. That in turn points to this larger article about problems R programmers find themselves facing. . How does one extricate oneself? Here were my steps.