[R] Plot lines whose angle and length depict vector quantities

[Bert Gunter]

On Fri, Sep 27, 2013 at 12:44 PM, Sarah Goslee <sarah.goslee at gmail.com> wrote:
> It's a straightforward trigonometry problem, isn't it?

Indeed! (  (r,theta) to (x,y) coordinates  ) . So I wonder if this is
a homework problem. If so, the OP should note that we try not to do
homework here.

Cheers,
Bert
>
> On Fri, Sep 27, 2013 at 2:56 PM, Conor Ryan <miolmor at gmail.com> wrote:
>> I am trying to plot points on a map for each ship locations (lat/long),
>> where
>> each point is a line whose angle (degrees) denotes ships heading and whose
>> line length denotes it's speed. Unfortunately arrows(); p.arrows (sfsmisc)
>> and ms.arrows (TeachingDemos) require start and end coordinates but I only
>> have a single coordinate and an angle to work with. Can you suggest any
>> other packages or commands that might allow me to plot this? Alternatively,
>> can anyone suggest a method of making 'angle' a vector quantity when using
>> the arrows function? Any advice would be much appreciated!
>>
>
> --
> Sarah Goslee
> http://www.functionaldiversity.org
>
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-- 

Bert Gunter
Genentech Nonclinical Biostatistics

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