I'm trying to analyze the following data set (sample): "ID" "adj.P.Val" "logFC" "Gene.symbol" "1419156_at" "5.32e-12" "2.6462565" "Sox4" "1433575_at" "5.32e-12" "3.9417089" "Sox4" "1428942_at" "2.64e-11" "3.9163618" "Mt2" "1454699_at" "2.69e-10" "1.8654677" "LOC100047324///Sesn1" "1416926_at" "3.19e-10" "2.172342" "Trp53inp1" "1422557_s_at" "1.58e-09" "2.9569254" "Mt1" etc.
using the following code: muscle = read.table(file="/Users/bob/Desktop/Muscle/musclesmall.txt", header = TRUE, colClasses = "character", fill = TRUE) upregulated_list = c() downregulated_list = c() nochange = c() p_thresh = 6.51e-06 x=1 while (x <= nrow(muscle)) { this_pval = muscle[x,"adj.P.Val"] this_M = muscle[x, "logFC"] if (muscle[x, "Gene.symbol"] == "") { x= x +1 } else {if ((this_M >= 1.0) & (this_pval <= p_thresh)) { upregulated_list <- append(upregulated_list, muscle[x,"Gene.symbol"],after=length(upregulated_list)) x = x +1} else {if ((this_M <= -1) & (this_pval <= p_thresh)) { downregulated_list <- append(downregulated_list, muscle[x,"Gene.symbol"],after=length(downregulated_list)) x = x+1 } else {if ((this_M > -1) & (this_M < 1)) { nochange <- append(nochange, muscle[x,"Gene.symbol"],after=length(nochange)) x = x+1} } } } } This process, however, goes line-by-line and the data has 22,000 rows, so running the process takes an enormous amount of time. Is there any way for me to do the analysis faster? -- View this message in context: http://r.789695.n4.nabble.com/Analyzing-large-files-faster-tp4633165.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.