--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MatrixEQTL/man/MatrixEQTL_cis_code.Rd	Fri Mar 12 08:12:46 2021 +0000
@@ -0,0 +1,129 @@
+\name{MatrixEQTL_cis_code}
+\alias{MatrixEQTL_cis_code}
+
+\title{Sample code for cis/trans-eQTL analysis with Matrix eQTL}
+\description{
+  The following code is the best starting point for those who want to perform cis-/trans-eQTL analysis with Matrix eQTL.
+}
+\references{
+  The package website: \url{http://www.bios.unc.edu/research/genomic_software/Matrix_eQTL/}
+}
+\seealso{
+  See \code{\link{Matrix_eQTL_engine}} for reference and other sample code.
+}
+\author{
+  Andrey Shabalin \email{ashabalin@vcu.edu}
+}
+\examples{
+# Matrix eQTL by Andrey A. Shabalin
+# http://www.bios.unc.edu/research/genomic_software/Matrix_eQTL/
+# 
+# Be sure to use an up to date version of R and Matrix eQTL.
+
+# source("Matrix_eQTL_R/Matrix_eQTL_engine.r");
+library(MatrixEQTL)
+
+## Location of the package with the data files.
+base.dir = find.package('MatrixEQTL');
+
+## Settings
+
+# Linear model to use, modelANOVA, modelLINEAR, or modelLINEAR_CROSS
+useModel = modelLINEAR; # modelANOVA, modelLINEAR, or modelLINEAR_CROSS
+
+# Genotype file name
+SNP_file_name = paste(base.dir, "/data/SNP.txt", sep="");
+snps_location_file_name = paste(base.dir, "/data/snpsloc.txt", sep="");
+
+# Gene expression file name
+expression_file_name = paste(base.dir, "/data/GE.txt", sep="");
+gene_location_file_name = paste(base.dir, "/data/geneloc.txt", sep="");
+
+# Covariates file name
+# Set to character() for no covariates
+covariates_file_name = paste(base.dir, "/data/Covariates.txt", sep="");
+
+# Output file name
+output_file_name_cis = tempfile();
+output_file_name_tra = tempfile();
+
+# Only associations significant at this level will be saved
+pvOutputThreshold_cis = 2e-2;
+pvOutputThreshold_tra = 1e-2;
+
+# Error covariance matrix
+# Set to numeric() for identity.
+errorCovariance = numeric();
+# errorCovariance = read.table("Sample_Data/errorCovariance.txt");
+
+# Distance for local gene-SNP pairs
+cisDist = 1e6;
+
+## Load genotype data
+
+snps = SlicedData$new();
+snps$fileDelimiter = "\t";      # the TAB character
+snps$fileOmitCharacters = "NA"; # denote missing values;
+snps$fileSkipRows = 1;          # one row of column labels
+snps$fileSkipColumns = 1;       # one column of row labels
+snps$fileSliceSize = 2000;      # read file in slices of 2,000 rows
+snps$LoadFile(SNP_file_name);
+
+## Load gene expression data
+
+gene = SlicedData$new();
+gene$fileDelimiter = "\t";      # the TAB character
+gene$fileOmitCharacters = "NA"; # denote missing values;
+gene$fileSkipRows = 1;          # one row of column labels
+gene$fileSkipColumns = 1;       # one column of row labels
+gene$fileSliceSize = 2000;      # read file in slices of 2,000 rows
+gene$LoadFile(expression_file_name);
+
+## Load covariates
+
+cvrt = SlicedData$new();
+cvrt$fileDelimiter = "\t";      # the TAB character
+cvrt$fileOmitCharacters = "NA"; # denote missing values;
+cvrt$fileSkipRows = 1;          # one row of column labels
+cvrt$fileSkipColumns = 1;       # one column of row labels
+if(length(covariates_file_name)>0) {
+  cvrt$LoadFile(covariates_file_name);
+}
+
+## Run the analysis
+snpspos = read.table(snps_location_file_name, header = TRUE, stringsAsFactors = FALSE);
+genepos = read.table(gene_location_file_name, header = TRUE, stringsAsFactors = FALSE);
+
+me = Matrix_eQTL_main(
+    snps = snps, 
+    gene = gene, 
+    cvrt = cvrt,
+    output_file_name      = output_file_name_tra,
+    pvOutputThreshold     = pvOutputThreshold_tra,
+    useModel = useModel, 
+    errorCovariance = errorCovariance, 
+    verbose = TRUE, 
+    output_file_name.cis  = output_file_name_cis,
+    pvOutputThreshold.cis = pvOutputThreshold_cis,
+    snpspos = snpspos, 
+    genepos = genepos,
+    cisDist = cisDist,
+    pvalue.hist = TRUE,
+    min.pv.by.genesnp = FALSE,
+    noFDRsaveMemory = FALSE);
+
+unlink(output_file_name_tra);
+unlink(output_file_name_cis);
+
+## Results:
+
+cat('Analysis done in: ', me$time.in.sec, ' seconds', '\n');
+cat('Detected local eQTLs:', '\n');
+show(me$cis$eqtls)
+cat('Detected distant eQTLs:', '\n');
+show(me$trans$eqtls)
+
+## Make the histogram of local and distant p-values
+
+plot(me)
+}