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agilp (version 3.8.0)

AAProcess: Extracts raw expression data from Agilent expression array scanner files.

Description

This function takes scanner "txt format" files produced by the Agilent microarray scanner, extracts just the raw median intensity values from the columns marked "gMedianSignal" or "rMedianSignal". Replicate probes are averaged. The expression data for each colour is written as separate txt tab delimited files with the same name as the original plus prefix rRaw_ or gRaw_. Probe names are in the first column, expression values in the second column.

Usage

AAProcess(input=file.path(system.file(package="agilp"),"input",""),output=file.path(system.file(package="agilp"),"output",""),s=9)

Arguments

input
full path of directory where input data files are put; default is a folder named input within the agilp package directory
output
full path of directory where output data files are put; default is a folder named output within the agilp package directory
s
number of header lines to skip when reading in scanner files. Default is 9

Value

rawdata files
The function writes a set of tab delimited txt files containing the raw data for each channel to directory defined by output. The raw data files are given the same name as the input data files with the prefix Rawg and Rawr for green and red channel respectively. The output files can be readily opened in Excel. In R each file is a dataframe, which contains probe names in first column, and expression data in second column. Replicate probes are averaged.

Details

The input directory must have ONLY the data files to be analysed.

References

In preparation

See Also

Loader filenamex IDswop Baseline Equaliser AALoess

Examples

Run this code

#This examples extracts expression data from two sample array scanner files which are found in the folder "scanner" within the agilp package extdata folder
#and places them in the folder output.
inputdir<-file.path(system.file(package="agilp"),"extdata","scanner","", fsep = .Platform$file.sep)
outputdir<-file.path(system.file(package="agilp"),"output", "", fsep = .Platform$file.sep)
AAProcess(input = inputdir, output = outputdir, s = 9)

## Not run: 
# #to remove these files again and empty the output directory use 
# unlink(paste(file.path(system.file(package="agilp"),"output",""),"*.*",sep=""), recursive=FALSE)
# 
# #The number of lines header to be skipped from scanner array files can be changed from the default value of 9 by setting variable s.
# AAProcess(input = inputdir, output = outputdir, s = 12)
#    ## End(Not run)
  

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