[R] plot with personalized axes

[Duarte Viana]

Hello all,

I want to plot some probability points (in scale 0-1), but the large
majority have extremely low probabilities.

Imagine I have the following vector

a<-c(0.0001,0.004,0.01,0.4)
plot(a)

When you plot it, obviously the three first points are not very
distinguishable. I would like to use a y-scale in which each "unity"
increases 10-fold from the previous one.

Say, a scale 10^n, where n=1,2,3... (equally spaced). For example,
c(0.00001,0.0001,0.001,0.01,0.1,1) equally spaced on the y-axis.

Some advice on that would be greatly appreciated.

Duarte Viana