轴位于中心的 R 图

默认情况下，R 中的笛卡尔轴位于图的底部和左侧。
如何使轴居中，如下图所示？

Example

## 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')

@ForrestRStevens 对我来说太快了，我太忙于尝试使用样条曲线来估计你的曲线:)

## 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

一般来说，您可以使用基本图形绘制几乎任何内容，但它通常比使用更复杂的包更复杂，因为您必须手动绘制所有内容。