text: user1806: We can use
  color yellow, resi 3
  color yellow, resi 3-8
  
  to colour one residue or a range of residues. But what if I want to colour residue 3-8 and 10-20, how to write it?
  Also, my protein has two chains, light chain (L) with 100 residues and heavy chain (H) with 100 residues. How to colour the residue 10-20, 30-40 of light chain, and the residue 5-10, 20-30 of heavy chain in one go?
  
  user203: Note: as I don't have any working version of pymol at the moment,
  I am not able to test the solution properly.
  However, an easy way is to first create a selection, and then to color it:
  select toBecolored, resi 3-8
  color yellow, toBecolored
  
  Regarding the L/H chain part, if they are effectively annotated as L and H, something like the following should work:
  select toBeColored, ((i. 10-20 or i. 30-40) and c. L ) or ((i. 5-10+20-30) and c. H)
  color yellow, toBeColored
  
  Combining both commands is probably possible as:
  color yellow, ((i. 10-20 or i. 30-40) and c. L ) or ((i. 5-10+20-30) and c. H)
  
  Pymol allows synonyms (eg. resi and i.  or chain and c.).
  The following pages may be also helpful:
  
  Pymol wiki: help on Selection
  SourceForge
  
  And the two following links, if you want to get a bit deeper in proper programming with python for pymol (as they can provide you with inspiration):
  
  Pymol wiki: plugins
  Pymol scripts
  
  
original_text: 1806: <p>We can use</p>
  
  <pre><code>color yellow, resi 3
  color yellow, resi 3-8
  </code></pre>
  
  <p>to colour one residue or a range of residues. But what if I want to colour residue 3-8 and 10-20, how to write it?</p>
  
  <p>Also, my protein has two chains, light chain (L) with 100 residues and heavy chain (H) with 100 residues. How to colour the residue 10-20, 30-40 of light chain, and the residue 5-10, 20-30 of heavy chain in one go?</p>
   203: <p>Note: as I don't have any working version of pymol at the moment,
  I am not able to test the solution properly.<br>
  However, an easy way is to first create a selection, and then to color it:</p>
  
  <pre><code>select toBecolored, resi 3-8
  color yellow, toBecolored
  </code></pre>
  
  <p>Regarding the L/H chain part, if they are effectively annotated as L and H, something like the following should work:</p>
  
  <pre><code>select toBeColored, ((i. 10-20 or i. 30-40) and c. L ) or ((i. 5-10+20-30) and c. H)
  color yellow, toBeColored
  </code></pre>
  
  <p>Combining both commands is probably possible as:</p>
  
  <pre><code>color yellow, ((i. 10-20 or i. 30-40) and c. L ) or ((i. 5-10+20-30) and c. H)
  </code></pre>
  
  <p>Pymol allows synonyms (eg. resi and i.  or chain and c.).</p>
  
  <p>The following pages may be also helpful:</p>
  
  <ul>
  <li><a href="https://pymolwiki.org/index.php/Selection_Algebra" rel="nofollow noreferrer">Pymol wiki: help on Selection</a></li>
  <li><a href="http://pymol.sourceforge.net/newman/user/S0220commands.htm" rel="nofollow noreferrer">SourceForge</a></li>
  </ul>
  
  <p>And the two following links, if you want to get a bit deeper in proper programming with python for pymol (as they can provide you with inspiration):</p>
  
  <ul>
  <li><a href="https://pymolwiki.org/index.php/Category:Plugins" rel="nofollow noreferrer">Pymol wiki: plugins</a></li>
  <li><a href="https://github.com/Pymol-Scripts/Pymol-script-repo" rel="nofollow noreferrer">Pymol scripts</a></li>
  </ul>
  