Hi everyone,

I'm trying to export the featureCounts output results of Rsubread to a .xls format (excel), but I'm not having success. I have got the counts of the reads from my RNASeq experiment, but I can't export the result. I used the command below, but it did not work. It appears that warning message.

I know the reportReads argument saves my output, but the generated files are so big and I know that exists a different and simpler way to do that. So, really appreciate if someone could help me.

Used function

>featureCounts(file="T_reesei_F24-2_GTGGCC_L008_R1_001.cleanreads.fastq.gz_tophat2/F24h-2_accepted_hits.bam",annot.ext = "TrireRUTC30_1_GeneCatalog_genes_20110526.fix2.gtf",isGTFAnnotationFile = TRUE,GTF.featureType = "CDS",GTF.attrType = "transcript_id")

GTF file

Output results

1664                                         +;+;+   3186
1665                                           +;+    234
1666                                             +   1362
 [ reached getOption("max.print") -- omitted 8186 rows ]

$targets
[1] "T_reesei_F24.2_GTGGCC_L008_R1_001.cleanreads.fastq.gz_tophat2.F24h.2_accepted_hits.bam"

$stat
                      Status
1                   Assigned
2       Unassigned_Ambiguity
3    Unassigned_MultiMapping
4      Unassigned_NoFeatures
5        Unassigned_Unmapped
6  Unassigned_MappingQuality
7 Unassigned_FragementLength
8         Unassigned_Chimera
  T_reesei_F24.2_GTGGCC_L008_R1_001.cleanreads.fastq.gz_tophat2.F24h.2_accepted_hits.bam
1                                                                               34914980
2                                                                                   8021
3                                                                                  88386
4                                                                               11354142
5                                                                                      0
6                                                                                      0
7                                                                                      0
8                                                                                      0

Used command to export

> res <- write.table(res$table, file = "F24.xls")

Warning message

Error in res$counts : object of type 'closure' is not subsettable

Thanks Gustavo Borin

You have to capture the output of featureCounts(), by assigning it to an object.

counts <- featureCounts(<arguments go here>)

Then if you look at the help for featureCounts, you will see this:

Value:

     A list with the following components:

  counts: a data matrix containing read counts for each feature or
          meta-feature for each library.

And you can write that out to a file.

Dear Gustavo Borin,

The 'reportReads' argument enables the detailed read assignment results to be saved into a file. The file includes overlapping features and other data for each read (each row corresponds a read). But I don't think that is what you want.

To save read counts generated from featureCounts, try the following command:

fc <- featureCounts(file="T_reesei_F24-2_GTGGCC_L008_R1_001.cleanreads.fastq.gz_tophat2/F24h-2_accepted_hits.bam",annot.ext="TrireRUTC30_1_GeneCatalog_genes_20110526.fix2.gtf",isGTFAnnotationFile = TRUE,GTF.featureType = "CDS",GTF.attrType = "transcript_id")

write.table(x=data.frame(fc$annotation[,c("GeneID","Length")],fc$counts,stringsAsFactors=FALSE),file="counts.txt",quote=FALSE,sep="\t",row.names=FALSE)

The generated 'counts.txt' file is a tab-delimited file which includes gene identifier, gene length and counts for each gene in each library.

Hope this helps.

Wei

Thank you so much James and Wei Shi. It was so simple to solve it! It worked successully!