[R] error bar position setting

[Yogesh Tiwari]

Hi,

I am using R on Windows XP.

I am using 'arrows' funtion to plot the variance as error bar, BUT error
bar goes only one side of the data point, I need to plot the error bar on
both side of the data point (plot is attached), I am using following
commands to plot,

plot(file3$lat,file3$STotwoKm,pch=21,cex=2.5,ylim=c(-0.2,2.5),xlim=c(-50,50),xlab=NA,ylab=NA,
col=1, xaxs="i",yaxs="i")

arrows(file3$lat, file3$var1, file3$lat,file3$STotwoKm, col=1, code=3,
angle=90, length=0.1)

Here:  lat=latitte (x-axis)
          STotwoKm = Data values (y-axis)
          Var1 = Variance

Kindly help how I can plot error bar on both side of data point,

Many thanks,

Regards,
Yogesh

-- 
Yogesh K. Tiwari (Dr.rer.nat),
Scientist,
Indian Institute of Tropical Meteorology,
Homi Bhabha Road,
Pashan,
Pune-411008
INDIA

Phone: 0091-99 2273 9513 (Cell)
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