+ Reply to Thread
Results 1 to 10 of 10

Coordinates Rotate and Translate

  1. #1
    Registered User
    Join Date
    03-18-2012
    Location
    ireland
    MS-Off Ver
    Excel 2007
    Posts
    6

    Coordinates Rotate and Translate

    I have a big list of coordinates, format (name,x,y,z), maybe a thousand long. Also it have a second list of coordinates that between 2 and 6 long, that are relative to each other, distances and angles locked.

    I want excel to compare my small group to the big list finding the closest matching set and translate and rotate the small set onto the new coordinates. I wanted to use the least squares method to find a match and keep a record of the tolerances of the match.

  2. #2
    Forum Expert shg's Avatar
    Join Date
    06-20-2007
    Location
    The Great State of Texas
    MS-Off Ver
    2003, 2010
    Posts
    40,678

    Re: Coordinates Rotate and Translate

    Welcome to the forum.

    You want to find the common transformation that most closely maps six of 1000 3D points to six given 3D points?

    That's a tall order. What's the genesis of the problem?
    Entia non sunt multiplicanda sine necessitate

  3. #3
    Registered User
    Join Date
    03-18-2012
    Location
    ireland
    MS-Off Ver
    Excel 2007
    Posts
    6

    Re: Coordinates Rotate and Translate

    genesis??

    Well I'm a surveyor, and I'm trying to improve my own skill-set, this is purely a stand alone problem that i posed myself. If i find an elegant solution I'll build upon it, for example last week I got excel to Reduce a .gsi file (csv containing horizontal angle,vertical angle, slope distances) format down to the Easting,Northing,Elevation corrected for Temp and Pressure. This is the next logical challenge. If i know where the control points need to be moved, then i can move the whole data set with it.

    Your understanding of the question is spot on, might even be better than my description. If i where programming this myself I'd get get the distance between each point in the small group and every other point in the small group, storing the answers. The starting on the the big list calculating the distances between each and every other point, and compare them to my stored distances, keeping note of the points that where within a set tolerance.This would filter the data down, allow for a second process to check all the angel and compare in the same way. Hope that makes sense.

    I know excel has all these add-ins like the solver and I'm eager to learn more mathematical robust ways of doing things

  4. #4
    Forum Expert shg's Avatar
    Join Date
    06-20-2007
    Location
    The Great State of Texas
    MS-Off Ver
    2003, 2010
    Posts
    40,678

    Re: Coordinates Rotate and Translate

    Is the rotation about a known axis?

    What are the few points and what are the many?

    How do you know that some subset of the many has a common transformation to the few?
    Last edited by shg; 03-18-2012 at 07:48 PM.

  5. #5
    Registered User
    Join Date
    03-18-2012
    Location
    ireland
    MS-Off Ver
    Excel 2007
    Posts
    6

    Re: Coordinates Rotate and Translate

    About Z, meaning x any y would change

    I'll create some test data and upload, making sure to have a identical set of points in full list

    It would be few translated it the many, and they are actually the same real world survey station observed for a different location, meaning the distances and angles between them remains the same

  6. #6
    Registered User
    Join Date
    03-18-2012
    Location
    ireland
    MS-Off Ver
    Excel 2007
    Posts
    6

    Re: Coordinates Rotate and Translate

    testdata.xlsx

    I've added a simple workbook with a large list of unique coordinates. and 6 other coordinates that are the result of a selection being rotated and translated out of place. Apologizes in the delay getting this done, had work needed doing.

    I'll put a few hours into this tomorrow evening, to see if I can get anywhere with it.

  7. #7
    Forum Expert shg's Avatar
    Join Date
    06-20-2007
    Location
    The Great State of Texas
    MS-Off Ver
    2003, 2010
    Posts
    40,678

    Re: Coordinates Rotate and Translate

    Is the translation in z only?

    It the rotation always about the z axis, or can it be about an axis parallel to z?

  8. #8
    Registered User
    Join Date
    03-18-2012
    Location
    ireland
    MS-Off Ver
    Excel 2007
    Posts
    6

    Re: Coordinates Rotate and Translate

    What i did was copy 6 coordinates, and rotated them about the origin, so there x,y values changed, then the translated them in both x and y also.

    The z values i left alone, so their identical to the original.

    Any x,y coordinates can be used as the center of rotation.

  9. #9
    Forum Expert shg's Avatar
    Join Date
    06-20-2007
    Location
    The Great State of Texas
    MS-Off Ver
    2003, 2010
    Posts
    40,678

    Re: Coordinates Rotate and Translate

    The z values i left alone, so their identical to the original.
    Right, but is that reflective of the actual data?

  10. #10
    Registered User
    Join Date
    03-18-2012
    Location
    ireland
    MS-Off Ver
    Excel 2007
    Posts
    6

    Re: Coordinates Rotate and Translate

    yes , i checked out distances,internal and external angles.

+ Reply to Thread

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts

Search Engine Friendly URLs by vBSEO 3.6.0 RC 1