如何在R中绘制一条与平滑曲线相切的直线？

# 生成示例数据
x <- seq(0, 10, length.out = 100)
y <- sin(x)

# 对数据进行平滑处理，生成平滑曲线
smoothed <- smooth.spline(x, y)

# 提取切点和切线方向点
index <- which.min(abs(smoothed$y - 0.5))  # 假设切点为平滑曲线上y值为0.5的点
tangent_point <- smoothed$x[index]
tangent_direction_point <- smoothed$y[index]

# 计算切线的斜率
slope <- (tangent_direction_point - smoothed$y[index-1]) / (tangent_point - smoothed$x[index-1])

# 计算切线的截距
intercept <- tangent_direction_point - slope * tangent_point

# 绘制平滑曲线
plot(x, y, type = "l", main = "Smoothed Curve")

# 绘制切线
abline(a = intercept, b = slope, col = "red")