thick plot lines

On Tue, 29 Apr 2003, Faheem Mitha wrote:

Dear People,

In a qqplot I am doing, I get lines/points that are very thick. I've tried
setting the lwd variable to 0.1, but it doesn't seem to have any effect.
Also, I have set the value of lty to dashed, but I still get dots. The
command looks like

qqplot(cdf.inv(seq(0,1,length=size),theta,pos,len),empmargdistvec(len,theta,pos,size),
      xlim=c(-theta,theta), ylim=c(-theta,theta), lwd=0.1,
      xlab="Marginal Quartiles", ylab="Empirical Marginal", col="red", lty="dashed")

I tried putting

par(lty="dashed",lwd=0.1)

before this, but this doesn't have any effect either.

I'm now wondering if I am doing something wrong. Does qqplot perhaps not
accept these parameters? What should I do to make the lines/points
thinner?

Thanks to the numerous people who replied. I stupidly did not realise that
the parameters lwd and lty would not apply unless I was plotting a line. I
think I assumed that the default points would turn into dashes and also
become smaller or something. :-) I should have realised that line type and
line width meant what they said. Excuse me, it was late at night.

Adding type="line" does indeed work. I suppose that if I wanted to shrink
the points I would use cex?

I think I need to look at a graphing tutorial. I see the "Contributed"
page has

    * Using R for Data Analysis and Graphics?  by John Maindonald.
    * Statistical Computing and Graphics Course Notes? by Frank E.
      Harrell.

Any other suggestions? Google (usually invaluable) is useless for this,
since searching for "R" is not very productive. Now if it was only called
SuperDuperStatPackage...

                                                   Faheem.