绘制编织错误：“无法启动 png() 设备”

Question

我正在使用 Rmarkdown 生成漂亮的文档（如使用 LaTex），但有一个我无法解决的问题。

我正在以下列方式打印图形：

```{r p(s|r)}

pleft=function(x, p=0.5){dnorm(x, mean=35, sd = 10)*p/(dnorm(x, mean=35, sd 
= 10)*p+dnorm(x, mean=65, sd = 10)*(1-p))}
pright=function(x, p=0.5){dnorm(x, mean=65, sd = 10)*(1-p)/(dnorm(x, 
mean=35, sd = 10)*p+dnorm(x, mean=65, sd = 10)*(1-p))}

pleft50= function(x){pleft(x, 0.5)}
pright50=function(x){pright(x, 0.5)}

curve(pleft50, from=-10, to=110, xlab="Firing Rate r (Hz)", ylab="p(s|r)", 
col="red", lwd=2)
curve(pright50, from=-10, to=110, xlab="Firing Rate r (Hz)", ylab="p(s|r)", 
col="blue", lwd=2, add=TRUE)
legend("right", legend = c("p(Left|r)","p(Right|r)"), col=c('red', 'blue'), 
lwd = 2)
title("Posteriors")

```

这在每个先例代码块和文档中都以相同的方式工作，但是现在当我编织文档时它会引发此错误：

png(..., res = dpi, units = "in") 中的错误：无法启动 png() 设备调用：... in_dir -> plot2dev -> do.call -> -> png 另外：警告消息: 1: 在 png(..., res = dpi, units = "in") : 无法打开文件 'ExSheet4_files/figure-html/name of my chunk-1.png' 2: 在 png(.. ., res = dpi, units = "in") : 打开设备失败

我已经尝试了任何我知道的东西，它会在curve(pleft50,...被调用时立即提出。

谢谢你的回答，对不起我的英语！

Answer 1

它不喜欢p(s|r)第一行中的 - 它试图创建一个用于写入的文件，但在那里失败了。如果删除它，例如：

---
title: "Untitled"
date: "April 14, 2018"
output:
  html_document: default
  word_document: default
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE)
```

```{r}
pleft=function(x, p=0.5){dnorm(x, mean=35, sd = 10)*p/(dnorm(x, mean=35, sd 
= 10)*p+dnorm(x, mean=65, sd = 10)*(1-p))}
pright=function(x, p=0.5){dnorm(x, mean=65, sd = 10)*(1-p)/(dnorm(x, 
mean=35, sd = 10)*p+dnorm(x, mean=65, sd = 10)*(1-p))}

pleft50= function(x){pleft(x, 0.5)}
pright50=function(x){pright(x, 0.5)}

curve(pleft50, from=-10, to=110, xlab="Firing Rate r (Hz)", ylab="p(s|r)", 
col="red", lwd=2)
curve(pright50, from=-10, to=110, xlab="Firing Rate r (Hz)", ylab="p(s|r)", 
col="blue", lwd=2, add=TRUE)
legend("right", legend = c("p(Left|r)","p(Right|r)"), col=c('red', 'blue'), 
lwd = 2)
title("Posteriors")
```

你得到这个：