[AstroPy] point in ellipse

gonghang.naoc ghang.naoc@gmail....
Thu Jan 31 21:26:45 CST 2013


Thanks.
I used that too,but it seems it could only be used in polygon and you
should know the vertices of the polygon?And you should convert ra&dec to
physical coordinate on ccd first?
Hang

On Fri, Feb 1, 2013 at 2:12 AM, Phil Rosenfield <
philrose@astro.washington.edu> wrote:

>
> I use nxutils for this:
> http://matplotlib.org/api/nxutils_api.html
>
>
> On Thu, Jan 31, 2013 at 10:00 AM, <astropy-request@scipy.org> wrote:
>
>> Send AstroPy mailing list submissions to
>>         astropy@scipy.org
>>
>> To subscribe or unsubscribe via the World Wide Web, visit
>>         http://mail.scipy.org/mailman/listinfo/astropy
>> or, via email, send a message with subject or body 'help' to
>>         astropy-request@scipy.org
>>
>> You can reach the person managing the list at
>>         astropy-owner@scipy.org
>>
>> When replying, please edit your Subject line so it is more specific
>> than "Re: Contents of AstroPy digest..."
>>
>>
>> Today's Topics:
>>
>>    1. point in ellipse (gonghang.naoc)
>>    2. Re: point in ellipse (Tim Jenness)
>>    3. Re: point in ellipse (Perry Greenfield)
>>    4. Re: point in ellipse (Tim Jenness)
>>    5. Re: point in ellipse (gonghang.naoc)
>>    6. Re: point in ellipse (gonghang.naoc)
>>
>>
>> ----------------------------------------------------------------------
>>
>> Message: 1
>> Date: Thu, 31 Jan 2013 02:33:51 +0800
>> From: "gonghang.naoc" <ghang.naoc@gmail.com>
>> Subject: [AstroPy] point in ellipse
>> To: astropy <astropy@scipy.org>
>> Message-ID:
>>         <
>> CABb23mvkRamvf-7m-atj+5moB3z2y4dRvvjQ8H3iUwoZNYxo6Q@mail.gmail.com>
>> Content-Type: text/plain; charset="utf-8"
>>
>> hi?everybody?
>>
>>      I believe many people here use ds9 and know  its region file
>> format.For example?we can make an ellipse if we know its center ra?dec and
>>
>> main aixs direction.Is there a pythonic way to judge whether a point is in
>> an ellipse if we know ra&dec of the point?
>>
>>      Thank you.
>>      Best wishes.
>>      Hang
>> -------------- next part --------------
>> An HTML attachment was scrubbed...
>> URL:
>> http://mail.scipy.org/pipermail/astropy/attachments/20130131/87c11093/attachment-0001.html
>>
>> ------------------------------
>>
>> Message: 2
>> Date: Wed, 30 Jan 2013 11:47:52 -0700
>> From: Tim Jenness <tim.jenness@gmail.com>
>> Subject: Re: [AstroPy] point in ellipse
>> To: "gonghang.naoc" <ghang.naoc@gmail.com>
>> Cc: astropy <astropy@scipy.org>
>> Message-ID:
>>         <CA+G92Rcuoc_kd+Uv32N58kj=
>> 7RhG2iwbUuUC84Z+QuSoJEh2CA@mail.gmail.com>
>> Content-Type: text/plain; charset="utf-8"
>>
>>
>> [now replying to list]
>>
>> You can use the Region class in pyast for that (it's not part of astropy).
>> It has support for all the STC regions.
>>
>>  https://github.com/timj/starlink-pyast
>>
>> AST is the library used internally by DS9.
>>
>> --
>> Tim Jenness
>>
>>
>> On Wed, Jan 30, 2013 at 11:33 AM, gonghang.naoc <ghang.naoc@gmail.com
>> >wrote:
>>
>> > hi?everybody?
>>
>> >      I believe many people here use ds9 and know  its region file
>> > format.For example?we can make an ellipse if we know its center ra?dec
>> and
>>
>> > main aixs direction.Is there a pythonic way to judge whether a point is
>> in
>> > an ellipse if we know ra&dec of the point?
>>
>> >      Thank you.
>> >      Best wishes.
>> >      Hang
>> >
>> > _______________________________________________
>> > AstroPy mailing list
>> > AstroPy@scipy.org
>> > http://mail.scipy.org/mailman/listinfo/astropy
>> >
>> >
>> -------------- next part --------------
>> An HTML attachment was scrubbed...
>> URL:
>> http://mail.scipy.org/pipermail/astropy/attachments/20130130/38b2b5d6/attachment-0001.html
>>
>> ------------------------------
>>
>> Message: 3
>> Date: Wed, 30 Jan 2013 13:48:01 -0500
>> From: Perry Greenfield <perry@stsci.edu>
>> Subject: Re: [AstroPy] point in ellipse
>> To: "gonghang.naoc" <ghang.naoc@gmail.com>
>> Cc: astropy <astropy@scipy.org>
>> Message-ID: <EBE9F98F-1ED3-4469-8F22-0732319F8405@stsci.edu>
>> Content-Type: text/plain; charset=utf-8
>>
>>
>> Sure.
>>
>> But I'm assuming you wanted more than that. I presume you are looking for
>> a function to test if a coordinate (or array of coordinates) lies inside
>> the ellipse or not. Yes, that can be done analytically. You want a python
>> function that does that specifically? (No, I don't have one handy, but it
>> shouldn't be hard to code).
>>
>> Perry
>>
>> On Jan 30, 2013, at 1:33 PM, gonghang.naoc wrote:
>>
>> > hi?everybody?
>> >      I believe many people here use ds9 and know  its region file
>> format.For example?we can make an ellipse if we know its center ra?dec and
>> main aixs direction.Is there a pythonic way to judge whether a point is in
>> an ellipse if we know ra&dec of the point?
>>
>> >      Thank you.
>> >      Best wishes.
>> >      Hang
>> >       _______________________________________________
>> > AstroPy mailing list
>> > AstroPy@scipy.org
>> > http://mail.scipy.org/mailman/listinfo/astropy
>>
>>
>>
>> ------------------------------
>>
>> Message: 4
>> Date: Wed, 30 Jan 2013 11:56:34 -0700
>> From: Tim Jenness <tim.jenness@gmail.com>
>> Subject: Re: [AstroPy] point in ellipse
>> To: Perry Greenfield <perry@stsci.edu>
>> Cc: astropy <astropy@scipy.org>
>> Message-ID:
>>         <
>> CA+G92Rc4YowNQ2kqpVzVW0n+Cs41YHwLk__kLyoeQSnD9HimYg@mail.gmail.com>
>> Content-Type: text/plain; charset="iso-8859-1"
>>
>>
>> On Wed, Jan 30, 2013 at 11:48 AM, Perry Greenfield <perry@stsci.edu>
>> wrote:
>>
>> > Sure.
>> >
>> > But I'm assuming you wanted more than that. I presume you are looking
>> for
>> > a function to test if a coordinate (or array of coordinates) lies inside
>> > the ellipse or not. Yes, that can be done analytically. You want a
>> python
>> > function that does that specifically? (No, I don't have one handy, but
>> it
>> > shouldn't be hard to code).
>> >
>> >
>> pyast has this built in. Create an ellipse object and then ask whether a
>> position (or set of positions) is inside or outside it.
>>
>> --
>> Tim Jenness
>> -------------- next part --------------
>> An HTML attachment was scrubbed...
>> URL:
>> http://mail.scipy.org/pipermail/astropy/attachments/20130130/6b2b8edf/attachment-0001.html
>>
>> ------------------------------
>>
>> Message: 5
>> Date: Thu, 31 Jan 2013 21:41:28 +0800
>> From: "gonghang.naoc" <ghang.naoc@gmail.com>
>> Subject: Re: [AstroPy] point in ellipse
>> To: Tim Jenness <tim.jenness@gmail.com>, astropy <astropy@scipy.org>
>> Message-ID:
>>         <
>> CABb23mtsqd6Y2-qE4Dgpm8KoHOhj-f6ftkoOFM84TNpT3b8QXQ@mail.gmail.com>
>> Content-Type: text/plain; charset="iso-8859-1"
>>
>>
>> Thank you very much. http://dsberry.github.com/starlink/node1.html is
>> helpful.
>> Hang
>>
>> On Thu, Jan 31, 2013 at 2:56 AM, Tim Jenness <tim.jenness@gmail.com>
>> wrote:
>>
>> >
>> >
>> >
>> > On Wed, Jan 30, 2013 at 11:48 AM, Perry Greenfield <perry@stsci.edu
>> >wrote:
>>
>> >
>> >> Sure.
>> >>
>> >> But I'm assuming you wanted more than that. I presume you are looking
>> for
>> >> a function to test if a coordinate (or array of coordinates) lies
>> inside
>> >> the ellipse or not. Yes, that can be done analytically. You want a
>> python
>> >> function that does that specifically? (No, I don't have one handy, but
>> it
>> >> shouldn't be hard to code).
>> >>
>> >>
>> > pyast has this built in. Create an ellipse object and then ask whether a
>> > position (or set of positions) is inside or outside it.
>> >
>> > --
>> > Tim Jenness
>> >
>> >
>> -------------- next part --------------
>> An HTML attachment was scrubbed...
>> URL:
>> http://mail.scipy.org/pipermail/astropy/attachments/20130131/edd5670b/attachment-0001.html
>>
>> ------------------------------
>>
>> Message: 6
>> Date: Thu, 31 Jan 2013 21:49:11 +0800
>> From: "gonghang.naoc" <ghang.naoc@gmail.com>
>> Subject: Re: [AstroPy] point in ellipse
>> To: astropy <astropy@scipy.org>
>> Message-ID:
>>         <CABb23mu6XjxxTk=
>> 8FD67BuJ_KwtymPK9uCutASitZUhJ9WfY7w@mail.gmail.com>
>> Content-Type: text/plain; charset="utf-8"
>>
>>
>> Thank you.oh, I thought a graphic way might be more convenient than a
>> mathematical way .I am lazy to calculate..
>> Hang
>>
>> On Thu, Jan 31, 2013 at 2:48 AM, Perry Greenfield <perry@stsci.edu>
>> wrote:
>>
>> > Sure.
>> >
>> > But I'm assuming you wanted more than that. I presume you are looking
>> for
>> > a function to test if a coordinate (or array of coordinates) lies inside
>> > the ellipse or not. Yes, that can be done analytically. You want a
>> python
>> > function that does that specifically? (No, I don't have one handy, but
>> it
>> > shouldn't be hard to code).
>> >
>> > Perry
>> >
>> > On Jan 30, 2013, at 1:33 PM, gonghang.naoc wrote:
>> >
>> > > hi?everybody?
>>
>> > >      I believe many people here use ds9 and know  its region file
>> > format.For example?we can make an ellipse if we know its center ra?dec
>> and
>>
>> > main aixs direction.Is there a pythonic way to judge whether a point is
>> in
>> > an ellipse if we know ra&dec of the point?
>>
>> > >      Thank you.
>> > >      Best wishes.
>> > >      Hang
>> > >       _______________________________________________
>> > > AstroPy mailing list
>> > > AstroPy@scipy.org
>> > > http://mail.scipy.org/mailman/listinfo/astropy
>> >
>> >
>> -------------- next part --------------
>> An HTML attachment was scrubbed...
>> URL:
>> http://mail.scipy.org/pipermail/astropy/attachments/20130131/227dd97f/attachment-0001.html
>>
>> ------------------------------
>>
>>
>> _______________________________________________
>> AstroPy mailing list
>> AstroPy@scipy.org
>> http://mail.scipy.org/mailman/listinfo/astropy
>>
>>
>> End of AstroPy Digest, Vol 76, Issue 11
>> ***************************************
>>
>
>
>
> --
> Phil Rosenfield
> Graduate Student: UW Astronomy
> Additional contact info:
> http://www.astro.washington.edu/philrose
>
> _______________________________________________
> AstroPy mailing list
> AstroPy@scipy.org
> http://mail.scipy.org/mailman/listinfo/astropy
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mail.scipy.org/pipermail/astropy/attachments/20130201/ad5f8908/attachment-0001.html 


More information about the AstroPy mailing list