r - Filter read_lines output?

Question

Given a read_lines output:

c("# This data file generated by ffffff at: Wed Jan 13 11:57:32 2011", 
"#", "# This file contains raw genotype data, including data that is not used in ffffff reports.", 
"# This data has undergone a general quality review however only a subset of markers have been ", 
"# individually validated for accuracy. As such, this data is suitable only for research, ", 
"# educational, and informational use and not for medical or other use.", 
"# ", "# Below is a text version of your data.  Fields are TAB-separated", 
"# Each line corresponds to a single SNP.  For each SNP, we provide its identifier ", 
"# (an rsid or an internal id), its location on the reference human genome, and the ", 
"# genotype call oriented with respect to the plus strand on the human reference sequence.", 
"# We are using reference human assembly build 37 (also known as Annotation Release 104).", 
"# Note that it is possible that data downloaded at different times may be different due to ongoing ", 
"# improvements in our ability to call genotypes. More information about these changes can be found at:", 
"# fffffffff", 
"# ", "# More information on reference human assembly builds:", 
"# ffffffffffffffff", 
"#", "# rsid\tchromosome\tposition\tgenotype", "rs548049170\t1\t69869\tTT", 
"rs13328684\t1\t74792\t--", "rs9283150\t1\t565508\tAA", "i713426\t1\t726912\t--", 
"rs116587930\t1\t727841\tGG", "rs3131972\t1\t752721\tAG", "rs12184325\t1\t754105\tCC", 
"rs12567639\t1\t756268\tAA", "rs114525117\t1\t759036\tGG", "rs12124819\t1\t776546\tAA", 
"rs12127425\t1\t794332\tGG", "rs79373928\t1\t801536\tTT", "rs72888853\t1\t815421\t--", 
"rs7538305\t1\t824398\tAC", "rs28444699\t1\t830181\tAA", "i713449\t1\t830731\t--", 
"rs116452738\t1\t834830\tGG", "rs72631887\t1\t835092\tTT", "rs28678693\t1\t838665\tTT", 
"rs4970382\t1\t840753\tCC", "rs4475691\t1\t846808\tCC", "rs72631889\t1\t851390\tGG", 
"rs7537756\t1\t854250\tAA", "rs13302982\t1\t861808\tGG", "rs376747791\t1\t863130\tAA", 
"rs2880024\t1\t866893\tCC", "rs13302914\t1\t868404\tTT", "rs76723341\t1\t872952\tCC", 
"rs2272757\t1\t881627\tAA", "rs35471880\t1\t881918\tGG")

I want to read_csv it but first I need to filter all the prefix starting with #.

Please advise how can I parse the file starting from the rows that don't start with #

标签： rparsingtidyversestringr

Answer 1

Your file appears to be a tab-separated data set with comments delimited by #. I'd suggest

readr::read_tsv("your_file", comment="#")

You might need col_names=FALSE too since it looks like your header row is also commented (this is awkward; it would be best if you can modify it upstream).