Hey,
Im using the function below to create minor tick marks on log scale. It
only plots every second marker, i.e. 10^0, 10^2 and so on. How do I get it
to plot at every interval? Thanks
minor.ticks.axis <- function(ax,n,t.ratio=0.5,mn,mx,...){
lims <- par("usr")
if(ax %in%c(1,3)) lims <- lims[1:2] else lims[3:4]
major.ticks <- pretty(lims,n=5)
if(missing(mn)) mn <- min(major.ticks)
if(missing(mx)) mx <- max(major.ticks)
major.ticks <- major.ticks[major.ticks >= mn & major.ticks <= mx]
labels <- sapply(major.ticks,function(i)
as.expression(bquote(10^ .(i)))
)
axis(ax,at=major.ticks,labels=labels,...)
n <- n+2
minors <- log10(pretty(10^major.ticks[1:2],n))-major.ticks[1]
minors <- minors[-c(1,n)]
minor.ticks = c(outer(minors,major.ticks,`+`))
minor.ticks <- minor.ticks[minor.ticks > mn & minor.ticks < mx]
axis(ax,at=minor.ticks,tcl=par("tcl")*t.ratio,labels=FALSE)}
x <- 10^(0:8)
y <- 1:9
plot(log10(x),y,xaxt="n",xlab="x",xlim=c(0,9))
minor.ticks.axis(1,9,mn=0,mx=8)
Thanks
--
Shane
[[alternative HTML version deleted]]
Shane I ran your code with debugging and found this for minor ticks [1]> minor.ticks [1] 1.000000 1.301030 1.477121 1.602060 1.698970 1.778151 1.845098 1.903090 1.954243 3.000000 3.301030 [12] 3.477121 3.602060 3.698970 3.778151 3.845098 3.903090 3.954243 5.000000 5.301030 5.477121 5.602060 [23] 5.698970 5.778151 5.845098 5.903090 5.954243 7.000000 7.301030 7.477121 7.602060 7.698970 7.778151 [34] 7.845098 7.903090 7.954243 Note how they go from 1-2, then 3-4, 5-6, etc skipping every other decade. Check the lines that produce minor.ticks David Stevens On 5/7/2014 10:32 AM, Shane Carey wrote:> Hey, > > Im using the function below to create minor tick marks on log scale. It > only plots every second marker, i.e. 10^0, 10^2 and so on. How do I get it > to plot at every interval? Thanks > > minor.ticks.axis <- function(ax,n,t.ratio=0.5,mn,mx,...){ > > lims <- par("usr") > if(ax %in%c(1,3)) lims <- lims[1:2] else lims[3:4] > > major.ticks <- pretty(lims,n=5) > if(missing(mn)) mn <- min(major.ticks) > if(missing(mx)) mx <- max(major.ticks) > > major.ticks <- major.ticks[major.ticks >= mn & major.ticks <= mx] > > labels <- sapply(major.ticks,function(i) > as.expression(bquote(10^ .(i))) > ) > axis(ax,at=major.ticks,labels=labels,...) > > n <- n+2 > minors <- log10(pretty(10^major.ticks[1:2],n))-major.ticks[1] > minors <- minors[-c(1,n)] > > minor.ticks = c(outer(minors,major.ticks,`+`)) > minor.ticks <- minor.ticks[minor.ticks > mn & minor.ticks < mx] > > > axis(ax,at=minor.ticks,tcl=par("tcl")*t.ratio,labels=FALSE)} > > x <- 10^(0:8) > y <- 1:9 > plot(log10(x),y,xaxt="n",xlab="x",xlim=c(0,9)) > minor.ticks.axis(1,9,mn=0,mx=8) > > > Thanks > >-- David K Stevens, P.E., Ph.D. Professor and Head, Environmental Engineering Civil and Environmental Engineering Utah Water Research Laboratory 8200 Old Main Hill Logan, UT 84322-8200 435 797 3229 - voice 435 797 1363 - fax david.stevens@usu.edu [[alternative HTML version deleted]]
On closer inspection, change n=5 to n=10 in major.ticks <- pretty(lims,n=5) Then, I get 10^0, 10^1, etc. with all the minors. Is this what you want? David On 5/7/2014 10:32 AM, Shane Carey wrote:> Hey, > > Im using the function below to create minor tick marks on log scale. It > only plots every second marker, i.e. 10^0, 10^2 and so on. How do I get it > to plot at every interval? Thanks > > minor.ticks.axis <- function(ax,n,t.ratio=0.5,mn,mx,...){ > > lims <- par("usr") > if(ax %in%c(1,3)) lims <- lims[1:2] else lims[3:4] > > major.ticks <- pretty(lims,n=5) > if(missing(mn)) mn <- min(major.ticks) > if(missing(mx)) mx <- max(major.ticks) > > major.ticks <- major.ticks[major.ticks >= mn & major.ticks <= mx] > > labels <- sapply(major.ticks,function(i) > as.expression(bquote(10^ .(i))) > ) > axis(ax,at=major.ticks,labels=labels,...) > > n <- n+2 > minors <- log10(pretty(10^major.ticks[1:2],n))-major.ticks[1] > minors <- minors[-c(1,n)] > > minor.ticks = c(outer(minors,major.ticks,`+`)) > minor.ticks <- minor.ticks[minor.ticks > mn & minor.ticks < mx] > > > axis(ax,at=minor.ticks,tcl=par("tcl")*t.ratio,labels=FALSE)} > > x <- 10^(0:8) > y <- 1:9 > plot(log10(x),y,xaxt="n",xlab="x",xlim=c(0,9)) > minor.ticks.axis(1,9,mn=0,mx=8) > > > Thanks > >-- David K Stevens, P.E., Ph.D. Professor and Head, Environmental Engineering Civil and Environmental Engineering Utah Water Research Laboratory 8200 Old Main Hill Logan, UT 84322-8200 435 797 3229 - voice 435 797 1363 - fax david.stevens at usu.edu