[[Rの備忘録]] # 始めに正規乱数を100 個生成 x <- rnorm(100) par(las = 1) # 軸の目盛を水平に hist(x, main = "N(0, 1) に従う100 個の乱数の分布", freq = F, col = "green", ylab = "確率密度", xlim = c(-4, 4), ylim = c(0,.6)) # 軸の範囲を指定 curve(dnorm, from = -4, to = 4, add = TRUE, # add はグラフへの上書きを許可 curve(dnorm, from = -4, to = 4, add = TRUE, lwd = 3, lty = 2, col = "red") # ここで add はグラフへの上書きを許可 # 凡例の作成 legend(-4, .55, legend= c("経験分布", "理論分布"), col = c("green", "red"), lwd = 5) # 図にキャプションを加える text(-4, .3, adj=0, cex = 1.3, expression(f(x) == # この部分は数式にギリシャ文字を使うための書式 frac(1, sigma * sqrt(2*pi)) ~~ e^{frac(-(x - mu)^2, 2 * sigma^2)})) # 図にキャプションを加える text(4, .3, adj=1, cex = 1.2, expression(paste("パラメータ", mu == 0, ", ", sigma == 1))) dev.off()