title: How can I plot a mathematical expression of two variables in python?
body: <p>I have a time- and depth-varying function, simplified to:</p>
  
  <pre><code>def f(z,t):
      return np.exp(-z)*np.sin(t-z)
  
  z = np.linspace(0,3000,num=3001)
  t = np.arange(0,40000,4000)
  </code></pre>
  
  <p>I want to plot the the result for all z at each time step in t, resulting in something like this:</p>
  
  <p><img src="https://i.stack.imgur.com/lt1tk.png" alt="enter image description here"></p>
  
  <p>but I don't know how. I'm sure it's very simple, but I'm not used to doing this in python.</p>