Hello, Back again,
I thought the problem was solved but I realised that the only reason I was getting the correct answer was because my data set happened to only have two "rfts" to choose from, so it looked correct. I have been using: onlyfirstresponseafterrft<-which(!diff(as.numeric(factor(Stat, levels = c("MagDwn", "Resp"))))) > onlyfirstresponseafterrft [1] 11 12 13 19 20 21 27 28 29 35 36 37 43 44 45 51 52 53 [19] 59 60 61 67 68 69 75 76 77 83 84 85 91 92 93 103 104 105 [37] 113 114 115 121 122 123 129 130 131 137 138 139 145 146 147 153 154 155 [55] 161 162 163 173 174 175 181 182 183 191 192 193 199 200 201 207 208 209 [73] 215 216 217 225 226 227 233 234 235 241 242 243 251 252 253 259 260 261 [91] 267 268 269 275 276 277 283 284 285 291 292 293 303 304 305 311 312 313 [109] 319 320 321 329 330 331 337 338 339 to get my results and what is being delivered is the rows at which a "resp" occurs after a "magdwn" except I only want the first "resp" after a mag down... This seems simple to figure out and I have tried a lot of things but its just not happening! Can anyone help me please? Thanks -- View this message in context: http://r.789695.n4.nabble.com/Selecting-the-first-occurrence-of-a-value-after-an-occurrence-of-a-different-value-tp3217340p3220788.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.