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

2013-09-28 Thread Conor Ryan
Hi Greg, thanks for your help. I found vectorFields, as suggested by Jim Lemon, in plotrix to be slightly easier (given my relatively basic R language knowledge!). Kind Regards, Conor On 27 September 2013 22:07, Greg Snow <538...@gmail.com> wrote: > The ms.arrows along with my.symbols in the Tea

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

2013-09-28 Thread Conor Ryan
Certainly not a homework question. Elementary questions do not necessarily indicate that one is a student! Always learning... Dr Conor Ryan On 28 September 2013 11:39, Patrick Burns wrote: > On 27/09/2013 21:01, Bert Gunter wrote: > >> On Fri, Sep 27, 2013 at 12:44 PM, Sarah Goslee >> wrote:

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

2013-09-28 Thread Conor Ryan
Hi Jim, vectorField worked a treat - thanks! On 28 September 2013 01:57, Jim Lemon wrote: > On 09/28/2013 04:56 AM, Conor Ryan 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 who

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

2013-09-28 Thread Patrick Burns
On 27/09/2013 21:01, Bert Gunter wrote: On Fri, Sep 27, 2013 at 12:44 PM, Sarah Goslee 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 homewo

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

2013-09-27 Thread Jim Lemon
On 09/28/2013 04:56 AM, Conor Ryan 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 (TeachingDemo

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

2013-09-27 Thread Greg Snow
The ms.arrows along with my.symbols in the TeachingDemos package does not require start and end points, it takes a single point along with the angle and length (and the length can be a single constant to have all the arrows the same length, or a variable to have different lengths). You can also se

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

2013-09-27 Thread Bert Gunter
On Fri, Sep 27, 2013 at 12:44 PM, Sarah Goslee 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,

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

2013-09-27 Thread Sarah Goslee
It's a straightforward trigonometry problem, isn't it? On Fri, Sep 27, 2013 at 2:56 PM, Conor Ryan 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