R 基本图形 : Annotate with logical symbols (and/or)

Question

我想添加逻辑符号 and (∧) 和 or (∨) 到 R 中的基础图.

我认为要走的路可能会使用表达式，但我无法弄清楚如何，因为他们的 unicode 代码 \u2227和 \u2228不工作。可能是因为我在 Windows 上(win 7、64 位)。

我有什么:

plot(1, 1, pch = "")
text(1, 1.2, 
     expression(paste("low ", italic(P), "(", italic(p), " and ", italic(q), 
        "), -1 SD")), cex = 1.2)
text(1, 0.8, 
     expression(paste("low ", italic(P), "(\u00ac", italic(p), " or ", italic(q), 
         "), -1 SD")), cex = 1.2)

我想替换文字 and和 or与他们的符号对应。

Answer 1

Symbol 字体映射的使用细节在:

?plotmath
?points # to which plotmath sends you for mapping of 'symbol' characters

# And I do not like the plotmath-paste function, 
# so translated to 'pure' expressions.
# The number arguments to symbol are numbers in octal.

plot(1, 1, pch = "")
text(1, 1.2, 
       expression(low ~italic(P)*"("*italic(p)~
                                   symbol("\332")~ italic(q)* 
                                  "), -1 SD"), 
       cex = 1.2)
text(1, 0.8, 
   expression(low~italic(P)* 
               "("*symbol("\330")*italic(p)~symbol("\331")~ italic(q)*
               "), -1 SD"),
    cex = 1.2 )

这是请求显示符号字形及其十进制索引的代码。 (警告:这是 Mac 上的 Symbol 字体。不能保证这在任何地方都是一样的。)您仍然需要转换为八进制以引用以使用上面看到的形式“\nnn”:

> as.octmode(216)
[1] "330"

TestChars <- function(sign = 1, font = 1, ...)
{
   MB <- l10n_info()$MBCS
   r <- if(font == 5) { sign <- 1; c(32:126, 160:254)
       } else if(MB) 32:126 else 32:255
   if (sign == -1) r <- c(32:126, 160:255)
   par(pty = "s")
   plot(c(-1,16), c(-1,16), type = "n", xlab = "", ylab = "",
        xaxs = "i", yaxs = "i",
        main = "Symbol Font, Decimal Indices")
   grid(17, 17, lty = 1) ; mtext(paste("MBCS:", MB))
   for(i in r) try(points(i%%16, i%/%16, pch = sign*i, font = font,...))

   for(i in r) try(text(x=i%%16, y=(i%/%16)-0.4, i, cex=0.5 , font = font,...))
}

TestChars(font = 5)