seg <- read.table("tmp.seg")
head(seg)
    id  chr   start      end test  ref       log2
2 114F chrY 9992443 10038173 2654 3818 -0.03
3 114F chrY 9969577 10015307  460 1286 -0.99
4 114F chrY 9946711  9992441  497 1348 -0.94
5 114F chrY 9923845  9969575  537 1254 -0.73
6 114F chrY 9900979  9946709 1040 2667 -0.86
7 114F chrY 9878113  9923843  700 2021 -1.03

p <- ggplot(seg) + geom_segment(aes(x=seg$start,y=seg$log2,xend=seg$end,yend=seg$log2,color=seg$log2),size=1) +
    facet_grid(id~chr,scales="free_x") +
      scale_color_gradient(limits=c(-1,1),low="blue", high="red") +
        theme(panel.background=element_rect(fill="white")) + ylim(c(-2,2))