I got rid of the quotes error by using single apostrophe quotes in notepad.
horAxisLims=c(0,7200) verData=c(1,365,809,1252,1753,2191,2922,3409,3896,4383,4819,5255,5691,6128,6564,7000) #not fussy horData=c(1,300,800,1200,1700,2100,2900,3400,3800,4300,4800,5200,5600,6100,6500,7000) #not at tics horTicLocs=c(1,365,809,1252,1753,2191,2922,3409,3896,4383,4819,5255,5691,6128,6564,7000) horLabels=c('1Yr','1Da','10.8Hr','7Hr','5Hr','4Hr','3Hr','2.57Hr','2.25Hr','2Hr','1.82Hr','1.67Hr','1.54Hr','1.43Hr','1.34Hr','1.25Hr') plot(horData,verData,xaxt='n',xlim=horAxisLims) axis(1,tick=TRUE,at=horTicLocs,labels=horLabels) The plotrix error is still there. Hurr -- View this message in context: http://r.789695.n4.nabble.com/Put-short-string-labels-vertically-near-tick-marks-on-bottom-axis-tp4690452p4690478.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.