R座標軸位於中心

Question

默認情況下，R中的笛卡爾座標軸位於座標圖的底部和左側。
如何使軸居中，如下圖所示？

例

## using; data; generated; by; bgoldst;; 
## estimate curve 
x <- seq(-1,1.5,0.1); 
y <- c(1.3,1.32,1.33,1.32,1.25,1.1,0.7,0.5,0.4,0.38,0.4,0.41,0.42,0.43,0.44,0.4,0.3,0.1,0,-0.05,-0.1,-0.15,-0.2,-0.24,-0.28,-0.3); 
f <- splinefun(x,y); 

## calculate precise points along estimated curve 
x <- seq(-1,1.5,0.01); 
y <- f(x); 
plot(x, y, type = 'l') 

Answer 1

我覺得像下面這樣做你會在基礎圖形喜歡什麼：

## Simulate your data: 
x <- seq(-3, 3, by=0.01) 
y <- 0.5*x - 0.3*x^2 + 0.4*x^3 

## Plot the polynomial function, removing axis ticks and bounding box, 
## as well as the axis labels: 
plot(x, y, 
    type="l", 
    xaxt='n', yaxt='n', 
    bty='n', 
    xlab='', ylab='', 
    col="blue") 

## Next add in your axis arrows: 
arrows(min(x), 0, max(x), 0, lwd=1, length=0.15) 
arrows(0, min(y), 0, max(y), lwd=1, length=0.15) 

## And plot your x/y labels. Note that if you want them 
## actually at the end of the arrows you would need to 
## remove the pos= argument and shorten your arrows by 
## a small amount. To match your original figure, you can 
## alter the x/y coordinate to be the max() instead. 
text(0, min(y), "y", pos=2) 
text(min(x), 0, "x", pos=3) 

個

Answer 2

@ForrestRStevens對我來說太快了，我太忙了嘗試使用花:)

## estimate curve 
x <- seq(-1,1.5,0.1); 
y <- c(1.3,1.32,1.33,1.32,1.25,1.1,0.7,0.5,0.4,0.38,0.4,0.41,0.42,0.43,0.44,0.4,0.3,0.1,0,-0.05,-0.1,-0.15,-0.2,-0.24,-0.28,-0.3); 
f <- splinefun(x,y); 

## calculate precise points along estimated curve 
x <- seq(-1,1.5,0.01); 
y <- f(x); 

## precompute limits 
xlim <- c(min(x),max(x)); 
ylim <- c(min(y)-0.4,max(y)+0.2); 

## set global plot params 
par(xaxs='i',yaxs='i',mar=c(1,1,3,3)+0.1); ## "internal" axis spacing, meaning no extended range, and slightly adjust margins 

## draw plot 
plot(NA,xlim=xlim,ylim=ylim,axes=F,ann=F); ## set plot bounds, no default ornaments 
arrows(c(0,xlim[1]),c(ylim[1],0),c(0,xlim[2]),c(ylim[2],0),0.05); ## draw custom axes 
mtext('y',3,1,at=0,las=1,cex=0.8,family='serif'); ## y label 
mtext('x',4,1,at=0,las=1,cex=0.8,family='serif'); ## x label 
lines(x,y,col='#aaaacc'); ## draw line on top 

一般估計你的曲線，你可以用圖形基地繪製幾乎任何東西，但是與使用更復雜的軟件包相比，這通常更爲複雜，因爲您必須手工繪製所有內容。