Re: A Question About Directive
- To: mathgroup at smc.vnet.net
- Subject: [mg111198] Re: A Question About Directive
- From: Murray Eisenberg <murray at math.umass.edu>
- Date: Fri, 23 Jul 2010 07:12:34 -0400 (EDT)
Good example! Of course one _could_ still dispense with Directive in the
first one, using instead...
Plot[{Cos[x], Sin[x]}, {x, 0, 2 Pi}, PlotStyle -> {{Thick, Red}}]
... with the nested PlotStyle value. And here, too, the point is that
Directive provides a convenience of eliminating nested braces.
Just because a function such as Directive in such situations is a mere
convenience and not indispensable does not militate against its
existence. After all, some other newer functions such as Total or
Accumulate are also dispensable but nonetheless conveniences.
If you want to stick with fewer functions, just go ahead and use the
nested parentheses.
On 7/22/2010 5:42 AM, Mark McClure wrote:
> On Mon, Jul 19, 2010 at 2:10 AM, Kevin J. McCann<kjm at kevinmccann.com> wrote:
>> I have noticed the use of Directive in some of the graphics examples
>> from Bob Hanlon, David Park, and others. I am curious about this
>> command, since it does not appear to do much that is new.
>> ...
>> So, what is the benefit of Directive?
>
> Try
> Plot[{Cos[x], Sin[x]}, {x, 0, 2 Pi},
> PlotStyle -> Directive[Thick, Red]]
> vs
> Plot[{Cos[x], Sin[x]}, {x, 0, 2 Pi},
> PlotStyle -> List[Thick, Red]]
>
> Mark McClure
>
--
Murray Eisenberg murray at math.umass.edu
Mathematics & Statistics Dept.
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University of Massachusetts 413 545-2859 (W)
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