使用R创建热图以绘制正值和负值

Question

I'm pretty new to R and I'm trying to create an heat map. This is an example of the data I created

Point         Distance
9273206       11
9273206       21
9273206       -25
9279872       -9
9279872       10
9770644        9
10315636       25
13144752        5
13257732       -3

A value in the Point column can occur multiple times. I'm trying to create a heat map which represents the unique value from the Point column (on a horizontal line), the value from the Distance column are plotted around it. The negative value on the left en the positive on the right. This is an example of what I'm trying to create:

http://i.imgur.com/AhVAxOQ.png

The black line in the middle represents the unique values from the Point column and the red lines the data points from the Distance column.

I have look around to find ways to plot this, but could not find anything. Could someone explain how to do this or give me a few tips. Or should I use something totally different?

thanks in advance for your help

Answer 1

If someone can help me out with the text issue, I came up with this.

plot(Point ~ Distance, data = yourData, pch = '.', cex = 10, 
     col = 'red', ylab = "", yaxt = "n", las = 1)
abline(v = 0)

Which produces the following plot.

The unique axis values were a bit more challenging. I thought text might be the right way to get there, but my result is a bit hard to read. Hopefully someone knows how to fix it.

 text(unique(dat$Point), labels = unique(dat$Point), 
      adj = c(1,2), pos = 2, offset = 0)