title: General approach of plotting specific solutions in a concrete time when using Matlab ODE solver for solving partial differential equations (PDEs)
body: <p><strong>Case</strong>: Based on the specified PDEs solution accuracy, the <code>ode15s</code> / <code>ode23s</code> optimises the computation time by reducing a number of time steps to a minimum of &quot;<strong>X</strong>&quot; time steps.</p>
  <p>As I don't know the value &quot;<strong>X</strong>&quot;, and therefore I have issues when trying to plot curves of solution that are equally distributed in time.</p>
  <p><strong>For example</strong>: Let's say that I specify the time vector from 0 to 60 s and after the ODE solver finds solutions, I would like to plot 7 curves of solution at 0, 10, 20, 30, 40, 50 and 60 s? How do I do that?</p>
  <p><strong>Issue</strong>: I can plot every, e.g. 40th 80th 120th 160th etc. curve of solution, however, I have no guarantee that the time difference between each is the same; in other words, it is guaranteed that the time difference between curves will be not equal.</p>
  <p>I hope my description makes sense!</p>
  <p><em>I don't think that there is need to include any part of code as the ODE solver has strict syntax and this is more like asking for advice in terms of general approach.</em></p>