HI, May be this helps: dat1<- read.table(text=" date1 time date timeSec topic pupilId correct 02/01/2013 14:58 02/01/2013 140323 fdp.fdp 40 TRUE 02/01/2013 14:59 02/01/2013 140372 fdp.fdp 150 TRUE 03/01/2013 11:23 03/01/2013 213833 fdp.percentage_calc_foundation 15 TRUE 03/01/2013 11:23 03/01/2013 213839 fdp.percentage_calc_foundation 57 TRUE 03/01/2013 11:24 03/01/2013 213845 fdp.percentage_calc_foundation 92 TRUE 03/01/2013 11:24 03/01/2013 213852 fdp.percentage_calc_foundation 65 TRUE 03/01/2013 11:24 03/01/2013 213855 fdp.percentage_calc_foundation 111 TRUE 03/01/2013 11:24 03/01/2013 213860 fdp.percentage_calc_foundation 34 TRUE 03/01/2013 11:24 03/01/2013 213864 fdp.percentage_calc_foundation 109 FALSE 03/01/2013 11:24 03/01/2013 213868 fdp.percentage_calc_foundation 148 FALSE 03/01/2013 11:24 03/01/2013 213877 fdp.percentage_calc_foundation 69 FALSE 03/01/2013 11:24 03/01/2013 213878 fdp.percentage_calc_foundation 61 TRUE 03/01/2013 11:24 03/01/2013 213878 fdp.percentage_calc_foundation 11 TRUE 03/01/2013 11:24 03/01/2013 213879 algebra.core.formulae 134 TRUE 03/01/2013 11:24 03/01/2013 213881 fdp.percentage_calc_foundation 63 TRUE 03/01/2013 11:24 03/01/2013 213886 fdp.percentage_calc_foundation 40 TRUE 03/01/2013 11:24 03/01/2013 213887 algebra.core.formulae 68 TRUE 03/01/2013 11:24 03/01/2013 213898 fdp.percentage_calc_foundation 109 TRUE 03/01/2013 11:24 03/01/2013 213899 algebra.core.formulae 111 TRUE 03/01/2013 11:25 03/01/2013 213901 algebra.core.formulae 101 FALSE 03/01/2013 11:25 03/01/2013 213924 fdp.percentage_calc_foundation 150 TRUE 03/01/2013 11:25 03/01/2013 213958 fdp.percentage_calc_foundation 77 TRUE 03/01/2013 11:25 03/01/2013 213959 fdp.percentage_calc_foundation 134 TRUE 03/01/2013 11:26 03/01/2013 213961 algebra.core.formulae 150 TRUE 03/01/2013 11:26 03/01/2013 214007 algebra.core.formulae 114 TRUE 03/01/2013 11:26 03/01/2013 214008 fdp.percentage_calc_foundation 55 FALSE 03/01/2013 11:26 03/01/2013 214009 fdp.percentage_calc_foundation 67 TRUE 03/01/2013 11:26 03/01/2013 214010 fdp.percentage_calc_foundation 24 TRUE 03/01/2013 11:26 03/01/2013 214014 algebra.core.formulae 114 TRUE 03/01/2013 11:26 03/01/2013 214014 algebra.core.equations 55 TRUE 03/01/2013 11:26 03/01/2013 214015 algebra.core.formulae 97 TRUE 03/01/2013 11:26 03/01/2013 214015 fdp.percentage_calc_foundation 154 FALSE 03/01/2013 11:26 03/01/2013 214017 algebra.core.formulae 21 FALSE 03/01/2013 11:26 03/01/2013 214017 fdp.percentage_calc_foundation 24 TRUE 03/01/2013 11:26 03/01/2013 214019 fdp.percentage_calc_foundation 149 TRUE 03/01/2013 11:26 03/01/2013 214019 fdp.percentage_calc_foundation 119 TRUE 03/01/2013 11:27 03/01/2013 214022 algebra.core.formulae 21 TRUE 03/01/2013 11:27 03/01/2013 214023 algebra.core.formulae 103 TRUE 03/01/2013 11:27 03/01/2013 214023 fdp.percentage_calc_foundation 55 TRUE 03/01/2013 11:27 03/01/2013 214024 fdp.percentage_calc_foundation 24 TRUE 03/01/2013 11:27 03/01/2013 214026 algebra.core.formulae 149 TRUE 03/01/2013 11:27 03/01/2013 214026 fdp.percentage_calc_foundation 154 TRUE 03/01/2013 11:27 03/01/2013 214027 algebra.core.formulae 24 TRUE 03/01/2013 11:27 03/01/2013 214078 algebra.core.equations 67 FALSE 03/01/2013 11:28 03/01/2013 214085 fdp.percentage_calc_foundation 119 TRUE 03/01/2013 11:28 03/01/2013 214085 fdp.percentage_calc_foundation 55 FALSE 03/01/2013 11:28 03/01/2013 214085 fdp.percentage_calc_foundation 149 TRUE 03/01/2013 11:28 03/01/2013 214086 algebra.core.formulae 67 FALSE 03/01/2013 11:29 03/01/2013 214169 algebra.core.formulae 92 TRUE 03/01/2013 11:29 03/01/2013 214172 algebra.core.formulae 15 TRUE 03/01/2013 11:29 03/01/2013 214172 algebra.core.equations 119 TRUE 03/01/2013 11:29 03/01/2013 214173 algebra.core.formulae 46 TRUE 03/01/2013 11:29 03/01/2013 214173 fdp.percentage_calc_foundation 146 TRUE ",sep="",header=TRUE,stringsAsFactors=FALSE) dat2<- data.frame(timestamp=as.POSIXct(paste(dat1[,1],dat1[,2]),format="%m/%d/%Y %H:%M"), dat1[,-c(1:2)])
library(xts) xt1<- xts(dat2[,-1],dat2[,1]) library(stringr) ##1st part nrow(xt1["2013-03-01 11:15/2013-03-01 11:28"]) #[1] 46 ##2nd part table(xt1["2013-03-01 11:15/2013-03-01 11:28","topic"]) # # algebra.core.equations algebra.core.formulae # 2 14 #fdp.percentage_calc_foundation # 30 ###3rd question Subxt1<-xt1["2013-03-01 11:15/2013-03-01 11:28"] #Based on number of correct responses vec1<-sort(with(Subxt1,tapply(as.logical(str_trim(correct)),list(pupilId),sum))) head(vec1,3) #101 148 69 # 0 0 0 tail(vec1,3) # 55 149 24 # 2 3 4 #Based on proportion of correct responses vec2<-with(Subxt1,tapply(as.logical(str_trim(correct)),list(pupilId),length)) vec2New<- vec2[names(vec1)] vec3<-sort(vec1/vec2New) head(vec3,3) #101 148 69 # 0 0 0 tail(vec3,3) #150 149 24 # 1 1 1 A.K. For date 03/01/2013 I need to find how many responses I have between 11.15 and 11.28. How do I go about producing another table just between that specified period and find the number of responses? (each input is a response) For this range I need to count how many different topics I have. The problem with the topic is that it is not a number, therefore I am not sure how to investigate it?? Finally, I need to find the 3 strongest and 3 weakest pupils in that same range on the proportion of correct responses given. Any help would be extremely appreciated!!! Table I have: timestamp date timeSec topic pupilId correct 02/01/2013 14:58 02/01/2013 140323 fdp.fdp 40 TRUE 02/01/2013 14:59 02/01/2013 140372 fdp.fdp 150 TRUE 03/01/2013 11:23 03/01/2013 213833 fdp.percentage_calc_foundation 15 TRUE 03/01/2013 11:23 03/01/2013 213839 fdp.percentage_calc_foundation 57 TRUE 03/01/2013 11:24 03/01/2013 213845 fdp.percentage_calc_foundation 92 TRUE 03/01/2013 11:24 03/01/2013 213852 fdp.percentage_calc_foundation 65 TRUE 03/01/2013 11:24 03/01/2013 213855 fdp.percentage_calc_foundation 111 TRUE 03/01/2013 11:24 03/01/2013 213860 fdp.percentage_calc_foundation 34 TRUE 03/01/2013 11:24 03/01/2013 213864 fdp.percentage_calc_foundation 109 FALSE 03/01/2013 11:24 03/01/2013 213868 fdp.percentage_calc_foundation 148 FALSE 03/01/2013 11:24 03/01/2013 213877 fdp.percentage_calc_foundation 69 FALSE 03/01/2013 11:24 03/01/2013 213878 fdp.percentage_calc_foundation 61 TRUE 03/01/2013 11:24 03/01/2013 213878 fdp.percentage_calc_foundation 11 TRUE 03/01/2013 11:24 03/01/2013 213879 algebra.core.formulae 134 TRUE 03/01/2013 11:24 03/01/2013 213881 fdp.percentage_calc_foundation 63 TRUE 03/01/2013 11:24 03/01/2013 213886 fdp.percentage_calc_foundation 40 TRUE 03/01/2013 11:24 03/01/2013 213887 algebra.core.formulae 68 TRUE 03/01/2013 11:24 03/01/2013 213898 fdp.percentage_calc_foundation 109 TRUE 03/01/2013 11:24 03/01/2013 213899 algebra.core.formulae 111 TRUE 03/01/2013 11:25 03/01/2013 213901 algebra.core.formulae 101 FALSE 03/01/2013 11:25 03/01/2013 213924 fdp.percentage_calc_foundation 150 TRUE 03/01/2013 11:25 03/01/2013 213958 fdp.percentage_calc_foundation 77 TRUE 03/01/2013 11:25 03/01/2013 213959 fdp.percentage_calc_foundation 134 TRUE 03/01/2013 11:26 03/01/2013 213961 algebra.core.formulae 150 TRUE 03/01/2013 11:26 03/01/2013 214007 algebra.core.formulae 114 TRUE 03/01/2013 11:26 03/01/2013 214008 fdp.percentage_calc_foundation 55 FALSE 03/01/2013 11:26 03/01/2013 214009 fdp.percentage_calc_foundation 67 TRUE 03/01/2013 11:26 03/01/2013 214010 fdp.percentage_calc_foundation 24 TRUE 03/01/2013 11:26 03/01/2013 214014 algebra.core.formulae 114 TRUE 03/01/2013 11:26 03/01/2013 214014 algebra.core.equations 55 TRUE 03/01/2013 11:26 03/01/2013 214015 algebra.core.formulae 97 TRUE 03/01/2013 11:26 03/01/2013 214015 fdp.percentage_calc_foundation 154 FALSE 03/01/2013 11:26 03/01/2013 214017 algebra.core.formulae 21 FALSE 03/01/2013 11:26 03/01/2013 214017 fdp.percentage_calc_foundation 24 TRUE 03/01/2013 11:26 03/01/2013 214019 fdp.percentage_calc_foundation 149 TRUE 03/01/2013 11:26 03/01/2013 214019 fdp.percentage_calc_foundation 119 TRUE 03/01/2013 11:27 03/01/2013 214022 algebra.core.formulae 21 TRUE 03/01/2013 11:27 03/01/2013 214023 algebra.core.formulae 103 TRUE 03/01/2013 11:27 03/01/2013 214023 fdp.percentage_calc_foundation 55 TRUE 03/01/2013 11:27 03/01/2013 214024 fdp.percentage_calc_foundation 24 TRUE 03/01/2013 11:27 03/01/2013 214026 algebra.core.formulae 149 TRUE 03/01/2013 11:27 03/01/2013 214026 fdp.percentage_calc_foundation 154 TRUE 03/01/2013 11:27 03/01/2013 214027 algebra.core.formulae 24 TRUE 03/01/2013 11:27 03/01/2013 214078 algebra.core.equations 67 FALSE 03/01/2013 11:28 03/01/2013 214085 fdp.percentage_calc_foundation 119 TRUE 03/01/2013 11:28 03/01/2013 214085 fdp.percentage_calc_foundation 55 FALSE 03/01/2013 11:28 03/01/2013 214085 fdp.percentage_calc_foundation 149 TRUE 03/01/2013 11:28 03/01/2013 214086 algebra.core.formulae 67 FALSE 03/01/2013 11:29 03/01/2013 214169 algebra.core.formulae 92 TRUE 03/01/2013 11:29 03/01/2013 214172 algebra.core.formulae 15 TRUE 03/01/2013 11:29 03/01/2013 214172 algebra.core.equations 119 TRUE 03/01/2013 11:29 03/01/2013 214173 algebra.core.formulae 46 TRUE 03/01/2013 11:29 03/01/2013 214173 fdp.percentage_calc_foundation 146 TRUE ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
