Results 1 to 5 of 5

Math Help - Please help in Least square

  1. #1
    Newbie
    Joined
    Sep 2009
    Posts
    3

    Please help in Least square

    I just have of about 14 points as a data
    I need to fiting them in a polynomial called Redlich- kister

    in the form


    y=x(1-x)∑(a0+a1(2x-1)+a2(2x-1)^2+a3(2x-1)^3)


    I tried to solve it in FORTRAN with least square but i dint got a good answer for that

    I got a program for solving the normal one as

    a0+a1(2x-1)+a2(2x-1)^2+a3(2x-1)^3)

    please help and if you have a code will much better

    thankssssssss
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Grand Panjandrum
    Joined
    Nov 2005
    From
    someplace
    Posts
    14,972
    Thanks
    4
    Quote Originally Posted by Abraham View Post
    I just have of about 14 points as a data
    I need to fiting them in a polynomial called Redlich- kister

    in the form


    y=x(1-x)∑(a0+a1(2x-1)+a2(2x-1)^2+a3(2x-1)^3)


    I tried to solve it in FORTRAN with least square but i dint got a good answer for that

    I got a program for solving the normal one as

    a0+a1(2x-1)+a2(2x-1)^2+a3(2x-1)^3)

    please help and if you have a code will much better

    thankssssssss
    Why not post this data.

    CB
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Sep 2009
    Posts
    3
    Quote Originally Posted by CaptainBlack View Post
    Why not post this data.

    CB
    Thanks for yr reply , I dont need to fit the only the data i have but i wana kindly to know how to solve that equation (kister eq.) by least square and find the concern cofficients
    the data is as following


    0.011 0.0218 0.037 0.0861 0.053 0.1654 0.061 0.2433 0.066 0.3101 0.069 0.374 0.072 0.4207 0.073 0.5003 0.07 0.5691 0.069 0.6326 0.067 0.7214 0.061 0.8072 0.049 0.86550.022 0.9573
    Last edited by CaptainBlack; September 10th 2009 at 07:55 PM.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Newbie
    Joined
    Aug 2009
    Posts
    9
    Quote Originally Posted by Abraham View Post
    Thanks for yr reply , I dont need to fit the only the data i have but i wana kindly to know how to solve that equation (kister eq.) by least square and find the concern cofficients
    the data is as following


    0.011 0.0218 0.037 0.0861 0.053 0.1654 0.061 0.2433 0.066 0.3101 0.069 0.374 0.072 0.4207 0.073 0.5003 0.07 0.5691 0.069 0.6326 0.067 0.7214 0.061 0.8072 0.049 0.86550.022 0.9573
    that is fitting the data!

    i recently implemented this myself (no you cannot have the code, sorry). wikipedia has the OLS equation:

    Linear regression - Wikipedia, the free encyclopedia
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Newbie
    Joined
    Sep 2009
    Posts
    3
    THanks for yr help
    I did answer the Qs and I found my mistake was on least square procedures ( just one iteration index missing ) not on the linear equations system solver

    so thanks for yr help
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 3
    Last Post: July 2nd 2011, 08:03 PM
  2. perfect square trinomial/square of binomial
    Posted in the Algebra Forum
    Replies: 2
    Last Post: March 3rd 2011, 05:02 PM
  3. Replies: 1
    Last Post: November 24th 2009, 09:17 AM
  4. Replies: 11
    Last Post: October 25th 2009, 07:45 PM
  5. [SOLVED] Deriving a square root under a square
    Posted in the Calculus Forum
    Replies: 4
    Last Post: September 29th 2007, 07:21 AM

Search Tags


/mathhelpforum @mathhelpforum