title: Multiple separate but similar ODE systems in R
body: <p>I'm fairly new to R and am facing the following problem:</p>
  
  <p>I have four different independent ODE systems such that</p>
  
  <pre><code>x' = a1*y - b1*x
  y' = a2*x - b2*y
  
  x' = a1 - b1*x/y
  y' = a2*x - b2*y
  
  x' = a1*y - b1*x
  y' = a2 - b2*y/x
  
  x' = a1 - b1*x/
  y' = a2 - b2*y/x
  </code></pre>
  
  <p>Each system shares some terms with another system. Now I'd like to solve them all and compare their time courses.</p>
  
  <p>Is there an efficient way of implementing this without having to type out every  single term? I should note that in reality I have much more ODEs than in this toy example.</p>
  
  <p>Thanks!</p>