Hi

When using following code in R, I am getting error

    lolliplot(mutation_data, fillCol="mutation_type", labelCol="amino_acid_change", proteinColour = "#ffffff", paletteB ="green", txtSize=3, txtAngle=20, host="dec2013.archive.ensembl.org")

    Using the following host: dec2013.archive.ensembl.org for biomaRt queries to change the ensembl annotation version alter this parameter!
    Querying biomaRt for transcript sequence
    Request to BioMart web service failed.
    The BioMart web service you're accessing may be down.
    Check the following URL and see if this website is available:
    http://dec2013.archive.ensembl.org:80/biomart/martservice?type=registry&requestid=biomaRt
    Error in if (!grepl(x = registry, pattern = "^\n*<MartRegistry>")) { : 
      argument is of length zero

How to solve this?

That particular Ensembl archive is no longer available.  You can view the list of available archives by following the link in the error message (you'll be redirected to an appropriate page) or by using the `listEnsemblArchives()` function in **biomaRt** e.g. 

    > biomaRt::listEnsemblArchives()
                 name     date                                url version current_release
    1  Ensembl GRCh37 Feb 2014          http://grch37.ensembl.org  GRCh37                
    2      Ensembl 95 Jan 2019 http://jan2019.archive.ensembl.org      95               *
    3      Ensembl 94 Oct 2018 http://oct2018.archive.ensembl.org      94                
    4      Ensembl 93 Jul 2018 http://jul2018.archive.ensembl.org      93                
    5      Ensembl 92 Apr 2018 http://apr2018.archive.ensembl.org      92                
    6      Ensembl 91 Dec 2017 http://dec2017.archive.ensembl.org      91                
    7      Ensembl 90 Aug 2017 http://aug2017.archive.ensembl.org      90                
    8      Ensembl 89 May 2017 http://may2017.archive.ensembl.org      89                
    9      Ensembl 88 Mar 2017 http://mar2017.archive.ensembl.org      88                
    10     Ensembl 87 Dec 2016 http://dec2016.archive.ensembl.org      87                
    11     Ensembl 86 Oct 2016 http://oct2016.archive.ensembl.org      86                
    12     Ensembl 85 Jul 2016 http://jul2016.archive.ensembl.org      85                
    13     Ensembl 84 Mar 2016 http://mar2016.archive.ensembl.org      84                
    14     Ensembl 83 Dec 2015 http://dec2015.archive.ensembl.org      83                
    15     Ensembl 82 Sep 2015 http://sep2015.archive.ensembl.org      82                
    16     Ensembl 81 Jul 2015 http://jul2015.archive.ensembl.org      81                
    17     Ensembl 80 May 2015 http://may2015.archive.ensembl.org      80                
    18     Ensembl 79 Mar 2015 http://mar2015.archive.ensembl.org      79                
    19     Ensembl 78 Dec 2014 http://dec2014.archive.ensembl.org      78                
    20     Ensembl 77 Oct 2014 http://oct2014.archive.ensembl.org      77                
    21     Ensembl 76 Aug 2014 http://aug2014.archive.ensembl.org      76                
    22     Ensembl 75 Feb 2014 http://feb2014.archive.ensembl.org      75                
    23     Ensembl 67 May 2012 http://may2012.archive.ensembl.org      67                
    24     Ensembl 54 May 2009 http://may2009.archive.ensembl.org      54    
