GSEA-R error R Mac OSX El Capitan

Question

Not sure how many people still use the R script for GSEA, but when I try and load the script and its functions:

GSEA.program.location <- ("file location of GSEA.1.0.R") 
source(GSEA.program.location, verbose=T, max.deparse.length=9999)

I get this error

'envir' chosen:<environment: R_GlobalEnv>
encoding = "native.enc" chosen
Error: '\%' is an unrecognized escape in character string starting ""Tag \%"

I believe I have to remove the backspace, but I have searched through GSEA.1.0.R, and the "source" function source code, and I can't find this '\\%'. What is it that I am doing wrong?

Session info:
R version 3.2.2 (2015-08-14)
Platform: x86_64-apple-darwin13.4.0 (64-bit)
Running under: OS X 10.11.1 (El Capitan)

locale:
[1] C/C/C/C/C/en_GB.UTF-8

attached base packages:
[1] stats graphics grDevices utils datasets methods base     

other attached packages:
[1] biomaRt_2.26.0  WGCNA_1.48  RSQLite_1.0.0 DBI_0.3.1 fastcluster_1.1.16  dynamicTreeCut_1.62

loaded via a namespace (and not attached):
 [1] reshape2_1.4.1        splines_3.2.2         lattice_0.20-33       colorspace_1.2-6      htmltools_0.2.6      
 [6] stats4_3.2.2          yaml_2.1.13           survival_2.38-3       XML_3.98-1.3          foreign_0.8-66       
[11] BiocGenerics_0.16.1   RColorBrewer_1.1-2    matrixStats_0.15.0    foreach_1.4.3         plyr_1.8.3           
[16] stringr_1.0.0         munsell_0.4.2         gtable_0.1.2          codetools_0.2-14      latticeExtra_0.6-26  
[21] Biobase_2.30.0        IRanges_2.4.1         doParallel_1.0.10     parallel_3.2.2        AnnotationDbi_1.32.0 
[26] preprocessCore_1.32.0 GSEABase_1.32.0       proto_0.3-10          Rcpp_0.12.1           acepack_1.3-3.3      
[31] xtable_1.8-0          scales_0.3.0          S4Vectors_0.8.1       Hmisc_3.17-0          graph_1.48.0         
[36] annotate_1.48.0       gridExtra_2.0.0       impute_1.44.0         ggplot2_1.0.1         digest_0.6.8         
[41] stringi_1.0-1         grid_3.2.2            tools_3.2.2           bitops_1.0-6          magrittr_1.5         
[46] RCurl_1.95-4.7        Formula_1.2-1         cluster_2.0.3         GO.db_3.2.2           MASS_7.3-45          
[51] rmarkdown_0.8.1       iterators_1.0.8       rpart_4.1-10          nnet_7.3-11   

Answer 1

These warnings occur when you have R version 2.5 and higher installed. To fix, remove the single backslashes in front of these characters as there is no need to escape them in R versions 2.5 and higher.