I'm trying to set up a zero matrix of variable length with two columns into which I can output the results of a while loop (with the intention of using it to store the step data from Euler's method with adjusted time-steps). The length will be determined by the number of iterations of the loop.
I'm wondering if there's a way I can do this while I'm running the loop or whether I need to set it up to begin with, and how to go about doing that.