[英]Is `expression(alpha)` (used in plotting) a “unevaluated expression”? How?
In order to write Greek letters / math on plot axes , we can use expression(alpha)
. 为了在绘图轴上写希腊字母/数学 ,我们可以使用
expression(alpha)
。 Is this the same as an unevaluated expression, as defined here ? 这是否与此处定义的未求值表达式相同? I don't see the connection between the two.
我看不到两者之间的联系。 Shouldn't
expression(alpha)
returns the unevaluated expression alpha
? expression(alpha)
不应返回未经评估的表达式alpha
吗? How did it become the symbol $\\alpha$? 它如何成为符号$ \\ alpha $?
No. This returns just alpha
: 不。这仅返回
alpha
:
quote(alpha)
An expression vector should be thought of as a type of list. 表达载体应被视为列表的一种。 The plotmath interpreter is set up to be a plotting subset of something like LaTeX, but in a much more limited way.
绘图算子解释器设置为LaTeX之类的绘图子集,但方式更为有限。 Review these pages:
查看以下页面:
?plotmath # really need to work through the examples; one by one
?bquote # exceedingly useful ... except with lattice functions
?substitute # several of the plotmath examples need `substitute`
?points # the example at the end.
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.