几行代码，一个逼真的圣诞树，圣诞快乐

圣诞快乐～

 上代码

library(tidyverse)
library(rlang)
source("R/grow_tree.R")

# step1、插上树枝
angle_fun1 <- function(angle) angle + c(-0.1 * pi, 0.1 * pi)
length_fun1 <- function(length) 0.85 * length
surv_fun1 <- function() 0.9

set.seed(12345)
tree1 <- grow_tree(n_iter = 10, angle_fun = angle_fun1(angle), length_fun = length_fun1(length),
    surv_fun = surv_fun1(), verbose = FALSE)

# step2、生出树叶
angle_fun2 <- function(angle, generation) {
    w <- 1 - 1/generation
    a0 <- rnorm(1, 0.12 * w * pi, 0.05 * w * pi)
    angle &#