contour2D 图的 x 和 y 轴值不正确
Incorrect x and y-axis values of contour2D plot
我想看看我的数据的密度,所以我用 cut
函数预处理的数据画了一个等高线图,这是我数据的一个小样本:
> z[1:2,]
pc2_cut
pc1_cut (-1.61,-1.45] (-1.45,-1.3] (-1.3,-1.15] (-1.15,-1] (-1,-0.851]
(-1.58,-1.38] 0 1 1 0 0
(-1.38,-1.18] 5 1 4 1 0
我使用了 plot3D
库并且,
> contour2D(z,border="black",xlab="PC1",ylab="PC2")
这是我得到的:
您可以看到 x 轴和 y 轴的值不正确,甚至不在间隔的中点附近。有谁知道如何纠正这个问题?
contour2D()
函数默认在 0 和 1 之间缩放轴。要获得不同的轴,您可以省略原始 contour2D()
调用中的轴,并使用 axis()
添加它们并指定 at
和 labels
。如果您使用 cut()
中的 factors
,您必须在绘图前将它们转换为数值。我在下面提供了一个示例,我在其中生成数据、绘制数据,然后在将因子转换为数值后调整轴标签。如果没有您的确切数据格式,我不知道从您的数据中提取刻度标记标签的最佳方法。
# library for plot
library(plot3D)
# setting seed and generating some data
set.seed(10)
#### storing data in matrix ####
datamatrix <- matrix(c(rnorm(500,-1,.4),rnorm(500,2,0.2),runif(500,-3,0),runif(500,0,3)),nrow=1000,ncol=2,byrow=F)
# locations of cuts
xcuts <- seq(min(datamatrix[,1]),max(datamatrix[,1]),length.out = 6)
ycuts <- seq(min(datamatrix[,2]),max(datamatrix[,2]),length.out = 6)
# calculating values for cutting
xvals <- cut(datamatrix[,1], xcuts)
yvals <- cut(datamatrix[,2], ycuts)
# initializing matrix to store count in each bin
z <- matrix(0,length(levels(yvals)),length(levels(xvals)))
for(i in 1:length(levels(xvals))){
for(j in 1:length(levels(yvals))){
z[j,i] <- length(intersect(which(xvals == levels(xvals)[i]),which(yvals == levels(yvals)[j])))
}
}
#### finding labels from factors cut ####
factsx <- levels(xvals) # factsx <- levels_pc2_cut # or something like that
xlabsFacts <- rep(NA,length(factsx))
for(i in 1:(length(factsx))){
comma_sep <- unlist(gregexpr(pattern =',',factsx[i])) # location of the comma in the factor
#taking section of text and converting to numbers
xlabsFacts[i] <- as.numeric(substr(factsx[i],2,comma_sep-1))
xlabsFacts[i+1] <- as.numeric(substr(factsx[i],comma_sep+1,nchar(factsx[i])-1))
}
factsy <- levels(yvals) # factsy <- levels_pc1_cut # or something like that
ylabsFacts <- rep(NA,length(factsy))
for(i in 1:(length(factsy))){
comma_sep <- unlist(gregexpr(pattern =',',factsy[i])) # location of the comma in the factor
#taking section of text and converting to numbers
ylabsFacts[i] <- as.numeric(substr(factsy[i],2,comma_sep-1))
ylabsFacts[i+1] <- as.numeric(substr(factsy[i],comma_sep+1,nchar(factsy[i])-1))
}
#### formatting plot ####
# contour plot without axes
contour2D(z
,yaxt='n' # no y axis ticks
,xaxt='n' # no x axis ticks
,ylab='y values' # y axis label
,xlab='x values' # x axis label
)
# adding x axis with tick marks
axis(side=1 # bottom
,at=seq(0,1,length.out = length(xlabsFacts)) # change 6 to number of tick marks you want
,labels=round(xlabsFacts,2) # change to labels for tick marks from your data
)
# adding x axis with tick marks
axis(side=2 # bottom
,at=seq(0,1,length.out = length(ylabsFacts)) # change 6 to number of tick marks you want
,labels=round(ylabsFacts,2) # change to labels for tick marks from your data
)
我想看看我的数据的密度,所以我用 cut
函数预处理的数据画了一个等高线图,这是我数据的一个小样本:
> z[1:2,]
pc2_cut
pc1_cut (-1.61,-1.45] (-1.45,-1.3] (-1.3,-1.15] (-1.15,-1] (-1,-0.851]
(-1.58,-1.38] 0 1 1 0 0
(-1.38,-1.18] 5 1 4 1 0
我使用了 plot3D
库并且,
> contour2D(z,border="black",xlab="PC1",ylab="PC2")
这是我得到的:
您可以看到 x 轴和 y 轴的值不正确,甚至不在间隔的中点附近。有谁知道如何纠正这个问题?
contour2D()
函数默认在 0 和 1 之间缩放轴。要获得不同的轴,您可以省略原始 contour2D()
调用中的轴,并使用 axis()
添加它们并指定 at
和 labels
。如果您使用 cut()
中的 factors
,您必须在绘图前将它们转换为数值。我在下面提供了一个示例,我在其中生成数据、绘制数据,然后在将因子转换为数值后调整轴标签。如果没有您的确切数据格式,我不知道从您的数据中提取刻度标记标签的最佳方法。
# library for plot
library(plot3D)
# setting seed and generating some data
set.seed(10)
#### storing data in matrix ####
datamatrix <- matrix(c(rnorm(500,-1,.4),rnorm(500,2,0.2),runif(500,-3,0),runif(500,0,3)),nrow=1000,ncol=2,byrow=F)
# locations of cuts
xcuts <- seq(min(datamatrix[,1]),max(datamatrix[,1]),length.out = 6)
ycuts <- seq(min(datamatrix[,2]),max(datamatrix[,2]),length.out = 6)
# calculating values for cutting
xvals <- cut(datamatrix[,1], xcuts)
yvals <- cut(datamatrix[,2], ycuts)
# initializing matrix to store count in each bin
z <- matrix(0,length(levels(yvals)),length(levels(xvals)))
for(i in 1:length(levels(xvals))){
for(j in 1:length(levels(yvals))){
z[j,i] <- length(intersect(which(xvals == levels(xvals)[i]),which(yvals == levels(yvals)[j])))
}
}
#### finding labels from factors cut ####
factsx <- levels(xvals) # factsx <- levels_pc2_cut # or something like that
xlabsFacts <- rep(NA,length(factsx))
for(i in 1:(length(factsx))){
comma_sep <- unlist(gregexpr(pattern =',',factsx[i])) # location of the comma in the factor
#taking section of text and converting to numbers
xlabsFacts[i] <- as.numeric(substr(factsx[i],2,comma_sep-1))
xlabsFacts[i+1] <- as.numeric(substr(factsx[i],comma_sep+1,nchar(factsx[i])-1))
}
factsy <- levels(yvals) # factsy <- levels_pc1_cut # or something like that
ylabsFacts <- rep(NA,length(factsy))
for(i in 1:(length(factsy))){
comma_sep <- unlist(gregexpr(pattern =',',factsy[i])) # location of the comma in the factor
#taking section of text and converting to numbers
ylabsFacts[i] <- as.numeric(substr(factsy[i],2,comma_sep-1))
ylabsFacts[i+1] <- as.numeric(substr(factsy[i],comma_sep+1,nchar(factsy[i])-1))
}
#### formatting plot ####
# contour plot without axes
contour2D(z
,yaxt='n' # no y axis ticks
,xaxt='n' # no x axis ticks
,ylab='y values' # y axis label
,xlab='x values' # x axis label
)
# adding x axis with tick marks
axis(side=1 # bottom
,at=seq(0,1,length.out = length(xlabsFacts)) # change 6 to number of tick marks you want
,labels=round(xlabsFacts,2) # change to labels for tick marks from your data
)
# adding x axis with tick marks
axis(side=2 # bottom
,at=seq(0,1,length.out = length(ylabsFacts)) # change 6 to number of tick marks you want
,labels=round(ylabsFacts,2) # change to labels for tick marks from your data
)