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

[Patrick Burns]

On 27/09/2013 21:01, Bert Gunter wrote:
> 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.

So that would make it unanimous that everyone here is trying
not to do homework.

Pat

>
> 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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>> and provide commented, minimal, self-contained, reproducible code.
>
>
>

-- 
Patrick Burns
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