taskGNU Astronomy Utilities - Tasks: task #14639, Program to identify points...

 
 

You are not allowed to post comments on this tracker with your current authentication level.

task #14639: Program to identify points inside/outside a region

Submitted by:  Mohammad Akhlaghi <makhlaghi>
Submitted on:  Sun 24 Sep 2017 11:26:37 PM UTC  
 
Should Start On: Sun 24 Sep 2017 10:00:00 PM UTCShould be Finished on: Sun 24 Sep 2017 10:00:00 PM UTC
Category: New programPriority: 5 - Normal
Item Group: EnhancementStatus: Postponed
Privacy: PublicPercent Complete: 0%
Assigned to: NoneOpen/Closed: Open
Effort: 0.00

Thu 28 Sep 2017 11:12:22 PM UTC, comment #1:

The region covered by most surveys can be represented with a convex polygon (see gal_polygon_ordered_corners).

However, some larger surveys (like the GOODS or CANDELS) can have saw-like borders which are represented by a concave polygon.

Therefore to be generic, this task is not independent of task #13658 (Work on concave polygons too). Once `gal_polygon_ordered_corners' also works on concave polygons (task #13658 is complete), the suggested program by this task will also work on any generic survey field.

Mohammad Akhlaghi <makhlaghi>
Project Administrator
Sun 24 Sep 2017 11:26:37 PM UTC, original submission:

Astronomical surveys are limited to a certain area of the sky (which can usually be represented nicely as the coordinates of a polygon).

While working on a catalog of objects, some of the objects might fall within the region of the survey we want to study and some might fall outside of it.

It would thus be very useful to have a program in Gnuastro that takes a region and a catalog of objects and identifies which of the objects are inside (or outside) that region.

Just as an initial brainstorm the program interface might look like the following:

The `region.txt' file could be a standard SAO DS9 region output which is very commonly used. It will work generally on any coordinate system (as long as the region and catalog have the same coordinates, like both are RA-Dec). But we must ensure that it works on RA-Dec coordinates (where the region/polygon cover pass the equator or celestial pole).

Ofcourse, the input region doesn't have to be a polygon, any user interface for any shape can be defined. Following ds9's region file convention should be a good start.

This task was defined during a discussion with Leindert Boogaard.

Mohammad Akhlaghi <makhlaghi>
Project Administrator

 

No files currently attached

 

Depends on the following items: None found

Items that depend on this one: None found

 

Carbon-Copy List
  • -unavailable- added by makhlaghi (Submitted the item)
  • -unavailable- added by makhlaghi
  •  

    Do you think this task is very important?
    If so, you can click here to add your encouragement to it.
    This task has 0 encouragements so far.

    Only logged-in users can vote.

     

    Please enter the title of George Orwell's famous dystopian book (it's a date):

     

     

    Follows 1 latest change.

    Date Changed By Updated Field Previous Value => Replaced By
    Sun 24 Sep 2017 11:26:37 PM UTCmakhlaghiCarbon-Copy-=>Added -unavailable-

    Back to the top


    Powered by Savane 3.1-cleanup1