Bootstrap

R:几个比较有意思的代码

n=50000;
r=0.7;r_e=(1-r*r)^.5;
X=rnorm(n);
Y=X*r+r_e*rnorm(n);
Y=ifelse(X>0,Y,-Y);
plot(X,Y,col="pink")

在这里插入图片描述

n=50000;
r=0.7;r_e=(1-r*r)^.5;
X=rnorm(n);
Y=X*r+r_e*rnorm(n);
Y=ifelse(X>0,Y,-Y);
a<-sample(c(2,6,7,8),50000,T)
b<-sample(c(76,79,86,69),50000,T)
plot(X,Y,col=0)
text(X,Y,"lOVE",col=a)

在这里插入图片描述

xrange = c(-15, 15)
yrange = c(0, 16)
plot(0, xlim = xrange, ylim = yrange, type = "n")
#plot(xrange, yrange, type="n", ann=FALSE, axes=FALSE)
yr = seq(yrange[1], yrange[2], len = 50)
offsetFn = function(y) {
2 * sin(0 + y/3)
}
offset = offsetFn(yr)
leftE = function(y) {
-10 - offsetFn(y)
}
rightE = function(y) {
10 + offsetFn(y)
}
xp = c(leftE(yr), rev(rightE(yr)))
yp = c(yr, rev(yr))
polygon(xp, yp, col = "#ffeecc", border = NA)
h = 9
xt = seq(0, rightE(h), len = 100)
yt = log(1 + log(1 + log(xt + 1)))
yt = yt - min(yt)
yt = h * yt/max(yt)
x = c(leftE(h), rightE(h), rev(xt), -xt)
y = c(h, h, rev(yt), yt)
polygon(x, y, col = "red", border = NA)

最后一张图不贴了,自行运行

悦读

道可道,非常道;名可名,非常名。 无名,天地之始,有名,万物之母。 故常无欲,以观其妙,常有欲,以观其徼。 此两者,同出而异名,同谓之玄,玄之又玄,众妙之门。

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