Thanks Marc, that has helped a lot. Say, for example, in a situation where I can't find out the highest value, is there any way to get R to automatically detect this and adjust the axis accordingly? I am planning to do this for many different stocks at once and dont wan't to have to define the highest value for each. I could set a standard axis value based on the max values of all stocks, however the detail will be lost for many of the less exploited species.
Marc Schwartz wrote: > > on 01/06/2009 09:07 PM jimdare wrote: >> Hi Everyone, >> >> Have created a bar plot of the data below using the following code: >> barplot(TACC,space=0,names.arg=Year). I now want to add a series of >> connected points to represent the catch. I tried to do this using >> line(Catch) or points(Catch), however both of these commands result in >> each >> data point being aligned with the right edge of each bar. I need them to >> be >> solid points in the centre of each bar, and for each point to be >> connected >> to its neighbour by a line. Another issue I have is when the points >> exceed >> the values for the bar graph (e.g. in 2004 and 2005 catch>TACC) R seems >> to >> cut them off, I need the axis to be expanded so they can be seen. I'm >> sure >> these are relatively simple problems but I am really stuck. Thanks very >> much for all your help, it is much appreciated. >> >> James >> >> DATA: >> >> Year Species Stock TACC Catch >> 1 2001 ORH OR1 5000 4687 >> 2 2002 ORH OR1 6000 3215 >> 3 2003 ORH OR1 7000 6782 >> 4 2004 ORH OR1 9000 10000 >> 5 2005 ORH OR1 9000 12000 > > One key point to note is that barplot() returns the bar midpoints. This > is noted in the help for barplot(). The bars are not centered on integer > axis values, so you need the returned values to place additional > annotation in the proper location relative to the bars. > > The other thing is to set the range of the y axis using the maximum > value in Catch, plus some fudge, so that the plot covers both sets of > data and has enough room for the additional points. > > Thus, presuming that your data is in a data frame called 'DF': > > mp <- barplot(DF$TACC, space = 0, names.arg = DF$Year, > ylim = c(0, 13000)) > > # Now use lines() to add Catch > lines(mp, DF$Catch, type = "b", pch = 19) > > See ?barplot, ?lines and ?points for more information. > > HTH, > > Marc Schwartz > > ______________________________________________ > 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. > > -- View this message in context: http://www.nabble.com/Bar-Plot-with-Connected-Points-on-1-Y-Axis-tp21324029p21339649.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.
