有关如何改进geom_text的分辨率以使分辨率与轴标签相当的建议？谢谢
df <- data.frame("x" = c(1,2,3,4),"y" = c(15,19,35,47))
p<-ggplot(df,aes(x,y))
p<- p + geom_point(size=1)
p<- p + geom_smooth(method="lm",se=FALSE,formula=y~x)
p<- p + xlab("Better Resolution")
p<- p +ylab("Better Resolution")
p<- p +opts(axis.title.x = theme_text(family="Times",face="bold",size=25,colour = "Black",vjust=0))
p<- p +opts(axis.title.y = theme_text(family="Times",angle =90,colour ="Black",vjust=0.4))
p<- p + geom_text(aes(x = 3.5,y = 37,label ="123456789"),size=12,parse = TRUE)
p
#The zoomed in text looks like this after saving using ggsave
#Information about my version of R and OS
sessionInfo()
R version 2.15.1 (2012-06-22)
Platform: x86_64-apple-darwin9.8.0/x86_64 (64-bit)
R.version
_
platform x86_64-apple-darwin9.8.0
arch x86_64
os darwin9.8.0
system x86_64,darwin9.8.0
status
major 2
minor 15.1
year 2012
month 06
day 22
svn rev 59600
language R
version.string R version 2.15.1 (2012-06-22)
nickname Roasted Marshmallows
##############
#The actual code I am using looks like this:
#function that creates the line equation
lm_eqn = function(df){
m = lm(y ~ x,df)
eq <- substitute(italic(y) == a + b %.% italic(x)*","~~italic(r)^2~"="~r2,list(a = format(coef(m)[1],digits = 2),b = format(coef(m)[2],r2 = format(summary(m)$r.squared,digits = 3)))
as.character(as.expression(eq))
}
#creates basic plot and adds a line
p<-ggplot(df,y))
p<- p + geom_point(alpha=1/10,colour="blue",size=5)
#controls background colours
p<-p + theme_bw()
#adds the labels,titles and makes them pretty
p<- p + geom_smooth(method="lm",formula=y~x,colour="black")
p<- p + xlab("Species similarity for site pair (Tsim variable 'a')")
p<- p +ylab("Trait similarity for site pairs (Tsim)")
p<- p +opts(title="Species vs. Trait combination similarity 2-5m")
p<- p +opts(plot.title = theme_text(family="Times",size=18,colour = "Black",vjust=1))
p<- p +opts(axis.title.x = theme_text(family="Times",size=15,vjust=0))
p<- p +opts(axis.title.y = theme_text(family="Times",colour = "Black",vjust=0.4))
#adds the equation
p<- p + geom_text(aes(x = 0.015,y = 0.08,label = lm_eqn(df)),size=6,family="Times",face="italic",parse = TRUE)
ggsave(p,file="tsim.a.0-2.pdf")
解决方法
为什么不使用ggsave保存屏幕上的情节.您在屏幕上看到的内容可能不一定是使用pdf或ps设备在输出图形中渲染的内容.
使用ggplot 0.9.1在Windows 7上使用R2.15.1的未编辑代码,我没有看到任何问题.
使用ggplot 0.9.1在Windows 7上使用R2.15.1的未编辑代码,我没有看到任何问题.
我使用ggsave保存了您的屏幕上的图形,并放大并且pdf看起来很棒：
使用ggsave(“plot.pdf”)(还有其他可选参数可以设置,包括保存为eps).这将保存最后一个图(默认情况下)到当前工作目录.检查情节.如果文本仍然看起来很有趣,我建议您的Times字体安装可能会有问题.
在这种情况下,您应该尝试省略字体规范,以便R选择它的默认字体系列.
你也应该改为主题而不是opts和element_text而不是theme_text(目前！).
**编辑**
好的,我想我已经找到了解决您的问题here感谢kohske和mbask.显然,更好的结果可以通过为您的标签创建一个数据框,并以这种方式传递给geom_text可以实现.
尝试使用：
df <- data.frame("x" = c(1,47))
lm_eqn = function(df){
m = lm(y ~ x,digits = 3)))
as.character(as.expression(eq))
}
### NEW ###
# Create a data frame to hold your label variables
data.label <- data.frame(
x = 0.015,label = c(lm_eqn(df))
)
#creates basic plot and adds a line
p<-ggplot(df,vjust=0.4))
### NEW
#### Change your call to geom_text ####
p<- p + geom_text(data = data.label,aes(x = x,y = y,label = label ),file="tsim.a.0-2.pdf")
我在Mac OS X 10.7.4和R 2.15.1上得到了这个：
