[R] how to print "<=" in plot title

[David Winsemius]

On Jun 28, 2011, at 2:52 PM, array chip wrote:

> Thank you David for the obvious fix and sorry for my lacking  
> innovative spirit,
> :-)
>
> Really, I know I haven't grasped the essence of plotting these math  
> symbols in
> R.

A lot of people (including me) have had trouble understanding to to  
write proper plotmath code. Here's my 10 cent version of an  
intro...things that were not clear to me on first, second, or third  
reading of the help(plotmath) page. (I am not saying these things are  
not in the page, just that they were not clear to me after multiple  
efforts at digestion. Searching r-help archives for worked examples  
was the most productive learning strategy.)

The stuff on left side of the table in the plotmath help page  
represent the "special words and symbols" and they need to be  
separated with the proper operators, since spaces are ignored (as  
actually happens in R parsing as well but we are generally shielded  
form that fact). Words other than these specials can be entered  
without quotes since expressions are not evaluated.  The list of greek  
letters is not complete. Not all of the script greeks work.  The "*"  
and "~" operators are the usual way to separate plotmath sub- 
expressions with either no-space or space displayed respectively.  
Commas are also special in separating individual expression values, so  
don't use them unless you want a multiple expression value (or need  
them inside a plotmath 'paste' or 'list'). You generally do not want  
multiple values of expression vector when constructing 'main' or 'sub'  
arguments, but may need them when constructing labels for plot axes.   
Only use quotes when they are really needed. You need to construct the  
arguments so that infix operations have flanking operands and notice  
that the plotmath paste function has no sep argument.


>
> John
>
>
>
> ----- Original Message ----
> From: David Winsemius <dwinsemius at comcast.net>
> To: array chip <arrayprofile at yahoo.com>
> Cc: Peter Ehlers <ehlers at ucalgary.ca>; R <r-help at r-project.org>
> Sent: Tue, June 28, 2011 11:50:02 AM
> Subject: Re: [R] how to print "<=" in plot title
>
>
> On Jun 28, 2011, at 2:42 PM, array chip wrote:
>
>> David,
>>
>> I tried your suggestion, still not working:
>>
>> x<-3
>> plot(1:10)
>> title(bquote(bold(x) <= bold(as.character(.(x)) )))
>>
>>
>> It prints x<=as.character(3) as title
>
> Kids these days! No innovative spirit. Why in my day... they would be
> jumping with the obvious fix to an elder's error.
>
> x<-3
> plot(1:10)
> title( bquote(bold(x) <= bold(.(as.character(x)) )))
>
> -- 
> David.
>>
>> Thanks
>>
>> John
>>
>>
>>
>> ----- Original Message ----
>> From: David Winsemius <dwinsemius at comcast.net>
>> To: array chip <arrayprofile at yahoo.com>
>> Cc: Peter Ehlers <ehlers at ucalgary.ca>; R <r-help at r-project.org>
>> Sent: Tue, June 28, 2011 11:30:23 AM
>> Subject: Re: [R] how to print "<=" in plot title
>>
>>
>> On Jun 28, 2011, at 2:19 PM, array chip wrote:
>>
>>> Thank you David and Bert.
>>>
>>> x<-3plot(1:10)
>>> title(bquote( x <= .(x) ))
>>>
>>> would do what I want. But I also want the title printed in bold
>>> font. so I
>>> tried
>>>
>>> x<-3
>>> plot(1:10)
>>> title(bquote(bold(x <= .(x)) ))
>>>
>>> But this did not print the "less than equal to" symbol and the
>>> number 3 (from
>>> variable x) in bold. Anyway to solve that?
>>
>> Nope. The Symbol font has no bold type face. Bolding of numbers
>> _can_ be done
>> inside bquote with bold(as.character(.(x)) )
>>
>> --David
>>>
>>> Thanks again!
>>>
>>> John
>>>
>>>
>>>
>>>
>>> ----- Original Message ----
>>> From: David Winsemius <dwinsemius at comcast.net>
>>> To: Peter Ehlers <ehlers at ucalgary.ca>
>>> Cc: array chip <arrayprofile at yahoo.com>; R <r-help at r-project.org>
>>> Sent: Tue, June 28, 2011 11:04:07 AM
>>> Subject: Re: [R] how to print "<=" in plot title
>>>
>>>
>>> On Jun 28, 2011, at 1:52 PM, Peter Ehlers wrote:
>>>
>>>> On 2011-06-28 10:25, array chip wrote:
>>>>> Hi, how can I print "<=" (I mean the symbol of just one
>>>>> character) in the
>>> main
>>>>> title of a plot?
>>>>>
>>>>> for example:
>>>>>
>>>>> plot(1:10, main=paste("x<=", x))
>>>>>
>>>>> where variable x is some number generated on the fly.
>>>>
>>>> x <- 2.718
>>>> plot(0, 0)
>>>> title(bquote( x %<=% .(x) ))
>>>
>>> I think John wants the mathematical symbol. As was pointed out in a
>>> question
>>> last week, the `<=` plotmath symbol needs to be flanked by operands.
>>> Non-printing operands can be created with the phantom function:
>>>
>>> title(main=expression(phantom("")<=phantom("")) )
>>>
>>> Contrary to Gunters's comment, this is probably going to work on
>>> all the three
>>> major OS platforms. It depends only on whether there is a Symbol
>>> font mapped
>> to
>>> the output device.
>>>>
>>>> ?plotmath
>>>
>>> Yes. The details are there.
>>>
>>>>
>>>> Peter Ehlers
>>>>
>>>
>>>
>>> David Winsemius, MD
>>> West Hartford, CT
>>
>> David Winsemius, MD
>> West Hartford, CT
>
> David Winsemius, MD
> West Hartford, CT

David Winsemius, MD
West Hartford, CT