As a beginner in Metabolomics and R, I'm trying to identify hundreds of peaks generated by LC-MS/MS. The xcms package tutorial shows how to process tandem MS data, but no information on identification is given. Another helpful tutorial, named "XCMS2: A Howto"(https://masspec.scripps.edu/xcms/download/XCMS2_howto.pdf), mentioned a function called "searchMetlin", which is not included in xcms package(1.47.2). So it puzzles me and need help to get me through it or provide some suggestions on how to identify peaks using tandem MS information.
The details about my R environment are listed below:
> sessionInfo() R version 3.2.3 (2015-12-10) Platform: x86_64-w64-mingw32/x64 (64-bit) Running under: Windows 7 x64 (build 7601) Service Pack 1 locale:  LC_COLLATE=Chinese (Simplified)_People's Republic of China.936  LC_CTYPE=Chinese (Simplified)_People's Republic of China.936  LC_MONETARY=Chinese (Simplified)_People's Republic of China.936  LC_NUMERIC=C  LC_TIME=Chinese (Simplified)_People's Republic of China.936 attached base packages:  parallel stats graphics grDevices utils  datasets methods base other attached packages:  xcms_1.47.2 Biobase_2.30.0  ProtGenerics_1.2.1 BiocGenerics_0.16.1  mzR_2.4.0 Rcpp_0.12.3 loaded via a namespace (and not attached):  tools_3.2.3 RColorBrewer_1.1-2 codetools_0.2-14  grid_3.2.3 lattice_0.20-33 >