MathGroup Archive 2011

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Joining points of ListPlot

  • To: mathgroup at smc.vnet.net
  • Subject: [mg117302] Re: Joining points of ListPlot
  • From: Antonio Mezzacapo <ant.mezzacapo at gmail.com>
  • Date: Mon, 14 Mar 2011 06:01:17 -0500 (EST)

Thank you for answering.

I don't have any functional form of this points. I have only this array of
points. Points on this array should be distributed *like* two crossing
functions as Sin[x] and Cos[x], but I don't know the functional form of
these functions.

All that I have is an array of points!
Because of the fact that these points distribute on the x-y cartesian plane
like two crossing functions, I cannot use "joined->true" because it gives me
strange results.

Thank you
Antonio

2011/3/13 Michael Stern <nycstern at gmail.com>

> Antonio,
>
> Some points of your question are unclear, but perhaps this will cover all
> relevant cases.
>
> 1. If you have functions, the simplest way is:
>
> Plot[{Sin[x], Cos[x]}, {x, 0, 2*Pi}]
>
> 2. You refer to "joined points," however, which suggests that you may be
> dealing with lists of points rather than functions. If so, you can do the
> same thing as follows:
>
> (* creating the two lists *)
> s1 = Table[Sin[x], {x, 0, 2*Pi, .1}];
> c1 = Table[Cos[x], {x, 0, 2*Pi, .1}];
>
> (* plot *)
> ListPlot[{s1, c1}, Joined -> True]
>
>
> 3. You refer to the points not being ordered, from which I take that one or
> both of the lists of plots has cartesian coordinates, not ordered by the
> independent variable. In this case, you can use Sort or SortBy to put them
> in order.
>
> (* creating two cartesian lists, neither of which is 'ordered' by the
> definition above *)
> s2 = RotateLeft[Table[{x, Sin[x]}, {x, 0, 2*Pi, .1}]];
> c2 = RotateRight[Table[{x, Cos[x]}, {x, 0, 2*Pi, .1}]];
>
> (* plot by sorted versions of these unordered lists *)
> ListPlot[{SortBy[s2, First], SortBy[c2, First]}, Joined -> True]
>
>
> Does that help?
>
> Michael
>
>
> On Mar 13, 2011, at 6:25 AM, Antonio Mezzacapo wrote:
>
> > Hi,
> > here's my problem:
> >
> > I have an array of data depicting two crossing functions (let's say like
> > Sin[x] and Cos[x]). How can I arrange them and make a joined points plot,
> > that joins only points belonging to the same function?
> > I remember you that the points of the two crossing functions are on the
> same
> > array and they are non-ordered.
> >
> > Thank you
> >
> > Antonio Mezzacapo
> >
>


  • Prev by Date: Re: what's new in 8.0.1?
  • Next by Date: Re: Joining points of ListPlot
  • Previous by thread: Re: Joining points of ListPlot
  • Next by thread: Re: Joining points of ListPlot