title: multiple iteration using dataframes to perform calculations
body: <p>I am quite new to python.</p>
  
  <p>how do i multiple iteration with dataframe in pandas</p>
  
  <p>I have 8760 values of sun zenith values---->theta_z<br>
  8760 values of sun azimuth values---->theta_a</p>
  
  <p>Now I have to iterate for two conditions  </p>
  
  <p>1)panel tilt (0-90)---> theta_t<br>
  2)panel azimuth (0-360)----->theta_azi</p>
  
  <p>I have to perform the below calculation  </p>
  
  <pre><code>x=arccos(cos(theta_z)*cos(theta_t)+sin(theta_z)*sin(theta_t)*cos(theta_a-theta_azi))
  
  
  
  for (i=0,i&lt;8761,i=i+1)  
      for (j=0,j&lt;361,j=j+1)  
            for (k=0,k&lt;91,k=k+1)  
  
                     x=....
  </code></pre>
  
  <p>Instead of using the below loops,how do i do the iteration in pandas if I have them as a seperate dataframe for each of them.I need to get 8760 x 361 x 91 values or 361 x 91 sets of 8760 values.</p>