Rosalind: Learn bioinformatics by programming it
So, I picked one at semi-random - <a href="http:&#x2F;&#x2F;rosalind.info&#x2F;problems&#x2F;prtm&#x2F;" rel="nofollow">http:&#x2F;&#x2F;rosalind.info&#x2F;problems&#x2F;prtm&#x2F;</a> and found a usability problem (a popup that doesn&#x27;t work; in FF or Safari) and a wrong example answer. Here&#x27;s the description.<p>&gt; Given: A protein string P of length at most 1000 aa.<p>&gt; Return: The total weight of P. Consult the monoisotopic mass table.<p>The &quot;monoisotopic mass table&quot; appears to be a link. I get a pop-up, but nothing appears in it, other than a spinner. I had to do a web search to find <a href="http:&#x2F;&#x2F;rosalind.info&#x2F;glossary&#x2F;monoisotopic-mass-table&#x2F;" rel="nofollow">http:&#x2F;&#x2F;rosalind.info&#x2F;glossary&#x2F;monoisotopic-mass-table&#x2F;</a> .<p>The page continues:<p>&gt; Sample Dataset - SKADYEK<p>&gt; Sample Output - 821.392<p>Using the monoisotopic mass table I computed:<p><pre><code>    &gt;&gt;&gt; d = {&#x27;A&#x27;: 71.03711, &#x27;C&#x27;: 103.00919, &#x27;D&#x27;: 115.02694,
    &#x27;E&#x27;: 129.04259, &#x27;F&#x27;: 147.06841, &#x27;G&#x27;: 57.02146,
    &#x27;H&#x27;: 137.05891, &#x27;I&#x27;: 113.08406, &#x27;K&#x27;: 128.09496,
    &#x27;L&#x27;: 113.08406, &#x27;M&#x27;: 131.04049, &#x27;N&#x27;: 114.04293,
    &#x27;P&#x27;: 97.05276, &#x27;Q&#x27;: 128.05858, &#x27;R&#x27;: 156.10111,
    &#x27;S&#x27;: 87.03203, &#x27;T&#x27;: 101.04768, &#x27;V&#x27;: 99.06841,
    &#x27;W&#x27;: 186.07931, &#x27;Y&#x27;: 163.06333}
    &gt;&gt;&gt; sum(d[c] for c in &quot;SKADYEK&quot;)
    821.3919199999999
</code></pre>
This matches the example. BUT!!!!<p>This is <i>NOT</i> the correct answer because as the expanded text says, &quot;the mass of a protein is the sum of masses of all its residues plus the mass of a single water molecule.&quot;<p>The table says &quot;the monoisotopic mass of water is considered to be 18.01056&quot; so<p><pre><code>    &gt;&gt;&gt; 821.3919199999999 + 18.01056
    839.40248
</code></pre>
This latter number matches the value given by <a href="https:&#x2F;&#x2F;web.expasy.org&#x2F;cgi-bin&#x2F;compute_pi&#x2F;pi_tool" rel="nofollow">https:&#x2F;&#x2F;web.expasy.org&#x2F;cgi-bin&#x2F;compute_pi&#x2F;pi_tool</a> .<p>Which means the example answer ... is wrong. Yes?<p>How (in)correct are the other answers? I-am-not-a-bioinformatics-programmer.