我想使用 ggplot 绘制多边形类型的空间图。其中绘制多边形,多边形的颜色由其权重决定。
示例数据框看起来像 - (这是数据文件完整的数据文件 https://dl.dropboxusercontent.com/u/55346033/sampleData.txt)
polyNr x y centroidX centroidY weight
1 4459425.25 5328202.595264193 4459675.25 5328202.595264193 -13.055709633886783
1 4459550.25 5328419.101615138 4459675.25 5328202.595264193 -13.055709633886783
1 4459800.25 5328419.101615138 4459675.25 5328202.595264193 -13.055709633886783
1 4459925.25 5328202.595264193 4459675.25 5328202.595264193 -13.055709633886783
1 4459800.25 5327986.088913247 4459675.25 5328202.595264193 -13.055709633886783
1 4459550.25 5327986.088913247 4459675.25 5328202.595264193 -13.055709633886783
2 4457550.25 5337512.3683548765 4457800.25 5337512.3683548765 -118.36760699572329
2 4457675.25 5337728.874705822 4457800.25 5337512.3683548765 -118.36760699572329
2 4457925.25 5337728.874705822 4457800.25 5337512.3683548765 -118.36760699572329
2 4458050.25 5337512.3683548765 4457800.25 5337512.3683548765 -118.36760699572329
2 4457925.25 5337295.862003931 4457800.25 5337512.3683548765 -118.36760699572329
2 4457675.25 5337295.862003931 4457800.25 5337512.3683548765 -118.36760699572329
3 4475175.25 5336862.849302039 4475425.25 5336862.849302039 -3.397375074455629
3 4475300.25 5337079.355652984 4475425.25 5336862.849302039 -3.397375074455629
3 4475550.25 5337079.355652984 4475425.25 5336862.849302039 -3.397375074455629
3 4475675.25 5336862.849302039 4475425.25 5336862.849302039 -3.397375074455629
3 4475550.25 5336646.342951093 4475425.25 5336862.849302039 -3.397375074455629
3 4475300.25 5336646.342951093 4475425.25 5336862.849302039 -3.397375074455629
4 4464675.25 5343358.039830423 4464925.25 5343358.039830423 -51.57522722796112
4 4464800.25 5343574.546181369 4464925.25 5343358.039830423 -51.57522722796112
4 4465050.25 5343574.546181369 4464925.25 5343358.039830423 -51.57522722796112
4 4465175.25 5343358.039830423 4464925.25 5343358.039830423 -51.57522722796112
4 4465050.25 5343141.533479477 4464925.25 5343358.039830423 -51.57522722796112
4 4464800.25 5343141.533479477 4464925.25 5343358.039830423 -51.57522722796112
3438 4459050.25 5338378.393758661 4459300.25 5338378.393758661 1.066256760712294
3438 4459175.25 5338594.900109607 4459300.25 5338378.393758661 1.066256760712294
3438 4459425.25 5338594.900109607 4459300.25 5338378.393758661 1.066256760712294
3438 4459550.25 5338378.393758661 4459300.25 5338378.393758661 1.066256760712294
3438 4459425.25 5338161.887407715 4459300.25 5338378.393758661 1.066256760712294
3438 4459175.25 5338161.887407715 4459300.25 5338378.393758661 1.066256760712294
我的步骤是——
-
将整个数据集分为十分位数:
breaks=unique(quantile(df$weight,probs=seq(0,1,by=0.1)))
df$deciles = cut(df$weight,breaks=breaks,include.lowest=TRUE)
-
色阶(我想要正数为红色,负数为绿色)
library(RColorBrewer)
colours=brewer.pal(name="RdYlGn", n=nlevels(df$deciles))
names(colours)=rev(levels(df$deciles))
-
plot
library(ggplot2)
ggplot(df,aes(x=x,y=y)) + geom_polygon(aes(group=polyNr,fill=factor(deciles))) + scale_fill_manual(values=colours)
这给了我一个情节 - 看起来像 -
但是,我的另一个要求是 - 我希望零为白色。一般来说,我可以使用
scale_fill_gradient2(low = muted("green"), mid = "white", high = muted("red"), midpoint = 0,)
但是,我不能不将它与我的离散比例一起使用。
首先,这可能吗?如果是,我怎样才能获得低高中颜色以及十分位数。如果这是重复的问题,请找到我错过的原始问题。
附: - 我对不同的数据集使用相同的代码,因此,设置手动色标并不可取。
EDIT -
对于颜色设置(红色、白色、绿色),我也尝试了 colorRampPalette。 (感谢@Pewi指出)
colours = colorRampPalette(c("red", "white", "green"))(11)
这给了我以下情节。
Still 零重量的白色设置是一个主要问题。我在基础包中也遇到了同样的问题。