Rosalind: Learn bioinformatics by programming it
So, I picked one at semi-random - <a href="http://rosalind.info/problems/prtm/" rel="nofollow">http://rosalind.info/problems/prtm/</a> and found a usability problem (a popup that doesn't work; in FF or Safari) and a wrong example answer. Here's the description.<p>> Given: A protein string P of length at most 1000 aa.<p>> Return: The total weight of P. Consult the monoisotopic mass table.<p>The "monoisotopic mass table" 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://rosalind.info/glossary/monoisotopic-mass-table/" rel="nofollow">http://rosalind.info/glossary/monoisotopic-mass-table/</a> .<p>The page continues:<p>> Sample Dataset - SKADYEK<p>> Sample Output - 821.392<p>Using the monoisotopic mass table I computed:<p><pre><code>    >>> d = {'A': 71.03711, 'C': 103.00919, 'D': 115.02694,
    'E': 129.04259, 'F': 147.06841, 'G': 57.02146,
    'H': 137.05891, 'I': 113.08406, 'K': 128.09496,
    'L': 113.08406, 'M': 131.04049, 'N': 114.04293,
    'P': 97.05276, 'Q': 128.05858, 'R': 156.10111,
    'S': 87.03203, 'T': 101.04768, 'V': 99.06841,
    'W': 186.07931, 'Y': 163.06333}
    >>> sum(d[c] for c in "SKADYEK")
    821.3919199999999
</code></pre>
This matches the example. BUT!!!!<p>This is <i>NOT</i> the correct answer because as the expanded text says, "the mass of a protein is the sum of masses of all its residues plus the mass of a single water molecule."<p>The table says "the monoisotopic mass of water is considered to be 18.01056" so<p><pre><code>    >>> 821.3919199999999 + 18.01056
    839.40248
</code></pre>
This latter number matches the value given by <a href="https://web.expasy.org/cgi-bin/compute_pi/pi_tool" rel="nofollow">https://web.expasy.org/cgi-bin/compute_pi/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.