尝试使用 Rmarkdown 编织我的文档时出错

Getting an error when trying to knit my document using Rmarkdown

我有这个代码:

```{r,echo=TRUE}
lg <- function(x, a = 1, b = 1){
  exp(a+b*x) / (1+exp(a+b*x))
}
```

```{r,echo=TRUE}
for (b in c(1:5)){
  curve(expr = lg(x, 1, b), from = -5, to = 5, n = 100, add= TRUE, col = b)
}
```

但是当我去编织文档时,它卡在了第 89 行,也就是以 for... 开头的那一行,我收到一条错误消息说,

error in plot.xy(xy.coords(x y) type = type ...)  plot.new has not been called yet 

Calls: <Anonymous> ... eval -> curve -> lines -> lines.default -> plot.xy

我需要 运行 这些作为单独的块,以便图表是分开的,但我不确定如何修复此错误以便我可以编织文档。

修改此内容可能对您有所帮助:

lg <- function(x, a = 1, b = 1){
  exp(a+b*x) / (1+exp(a+b*x))
}
plot(NA, xlim = c(-5, 5), ylim = c(0, 1))
for (b in c(1:5)){
  curve(expr = lg(x, 1, b), from = -5, to = 5, n = 100, add= TRUE, col = b)
}