Hello, I am attempting to use R to query KEGG in order to find cpd IDs from neutral masses and eventually link these cpd IDs up to the pathways they are part of. I have several question that are listed after the example R code for the problems. Finally, at the end is what I think the ideal result would look like, that I cannot achieve. ######### session info ################## > sessionInfo() R version 2.4.0 (2006-10-03) i386-pc-mingw32 attached base packages: [1] "methods" "stats" "graphics" "grDevices" "utils" "datasets" "base" other attached packages: KEGG KEGGSOAP SSOAP RCurl XML "1.8.1" "1.9.1" "0.4-0" "0.8-0" "1.2-0" #################################################################### #Example R code for the problem I am having.# cpdID<-c(1,2,3,4,5,6) mass<-c(129.0426, 147.0532, 208.0848, 220.0848, 204.0899, 777.0317) RT<-c(1,2,3,4,5,6) ppmerror<-c(4,11,75,7,21,55) floatmass=NULL for (i in 1:length(cpdID)) { floatmass[i]<-if(ppmerror[i]<10) {1e-5*mass[i]} else{(ppmerror[i]/10^6)*mass[i]} } testdata<-as.data.frame(cbind(cpdID, mass, RT, ppmerror, floatmass)) library(KEGGSOAP) library(KEGG) KEGGID=NULL for (i in 1:length(testdata$cpdID)) { KEGGID[i]<-(search.compounds.by.mass(testdata$mass[i], testdata$floatmass[i])) } KEGGID tt<-cbind(KEGGID,testdata) ### this cbind does not work vectors are different sizes #### ###the objects below contain the full query results for each output in the loop above#### a<-t(as.data.frame(search.compounds.by.mass(129.0426,0.00129))) b<-t(as.data.frame(search.compounds.by.mass(147.0532,0.00161))) c<-t(as.data.frame(search.compounds.by.mass(208.0848,0.0156))) d<-t(as.data.frame(search.compounds.by.mass(220.0848,0.0022))) e<-t(as.data.frame(search.compounds.by.mass(204.0899,0.0042))) f<-t(as.data.frame(search.compounds.by.mass(777.0317,0.0427))) Problem #1 (probably has to do with how R works) Each queried mass except the last which has none has more than one annotation. Why does R only fill one (the first annotation returned of the query result, while truncating the rest) value in the KEGGID loop? How can I produce an output that will allow all the annotations for each mass to be hooked back up to the table testdata using a loop that can cycle through the table testdata? Problem #2 What does R consider an output value from a KEGG query to be? If I am going to solve problem 1 I need some way to fill in the missing annotation where nothing is returned from KEGG. Currently this data is skipped causing output to be too short. How can I write an if else statement (or something similar) to fill in NA or a phrase like "no hit" when no annotation is present? I was thinking that something like the loop below, but i dont know what "X" should be in the IF statement KEGGID2=NULL for (i in 1:length(testdata$cpdID)) { KEGGID2[i]<-if((search.compounds.by.mass(testdata$mass[i], testdata$floatmass[i]))==X) {search.compounds.by.mass(testdata$mass[i], testdata$floatmass[i]} else{NA} } #Ideal result, that I cannot achieve with my knowledge of R# a11<-c(1, 129.0426,10, 4, 0.001290426,"cpd:C01877","cpd:C01879","cpd:C02237","cpd:C02238","cpd:C 04281", "cpd:C04282","blank","blank","blank","blank","blank") b11<-c(2, 147.0532,15,11, 0.001617585,"cpd:C00025","cpd:C00217", "cpd:C00302", "cpd:C00979", "cpd:C03618","cpd:C03790","cpd:C05574", "cpd:C05938", "cpd:C05941", "cpd:C12269","blank") c11<-c(3, 208.0848, 20,75, 0.015606360,"cpd:C00328", "cpd:C01484", "cpd:C01718", "cpd:C02381", "cpd:C05610", "cpd:C05647", "cpd:C06487", "cpd:C09816", "cpd:C11433", "cpd:C11690", "cpd:C15589") d11<-c(4,220.0848,4,7,0.002200848,"cpd:C00643","cpd:C01017","cpd:C0998 5","blank","blank","blank","blank","blank","blank","blank","blank") e11<-c(5,204.0899,7,21, 0.004285888,"cpd:C00078", "cpd:C00525", "cpd:C00806", "cpd:C07839", "cpd:C10743", "cpd:C10968", "cpd:C14916","blank","blank","blank","blank") f11<-c(6,777.0317, 11, 55, 0.042736744,"no hit","blank","blank","blank","blank","blank","blank","blank","blank"," blank","blank") ideal<-rbind(a11,b11,c11,d11,e11,f11) colnames(ideal)<-c("cpdID","mass","RT","ppmerror","floatmass","cpd1"," cpd2","cpd3","cpd4","cpd5","cpd6","cpd7","cpd8","cpd9","cpd10","cpd11" ) ideal Thank you, Alan Smith University of Wisconsin-Madison