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本帖最后由 genechip 于 2011-10-17 10:50 编辑
数据量小的时候,一般的散点图矩阵足矣,但是数据量大的时候,很多点重合在一起,效果很差。因此,此时引入颜色来标记散点密度是个不错的想法。效果如下:
library(IDPmisc)
library(SwissAir) # data for the example
## prepare the data
Ox <- AirQual[,c("ad.O3","lu.O3","sz.O3")] +
AirQual[,c("ad.NOx","lu.NOx","sz.NOx")] -
AirQual[,c("ad.NO","lu.NO","sz.NO")]
names(Ox) <- c("ad","lu","sz")
## draw graph
ipairs(Ox, ztransf = function(x){x[x<1] <- 1; log2(x)})
转自http://cos.name/cn/topic/16730#post-16730 |
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