Welcome to the NavList Message Boards.

NavList:

A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Message:αβγ
Message:abc
Add Images & Files
    or...
       
    Reply
    Re: No Two-Body Fix Problems
    From: John Karl
    Date: 2009 Nov 5, 18:51 -0800

    Peter,  OK, good.
    
    I should also mention that there's no need to use the other solutions
    to the inverse cosines in Eq. 7.5a&b (i.e., like 180-A) because those
    solutions just switch (A+B) and (A-B) when substituted into cos(A-B)
    in Eq. 7.5d (maybe this isn't obvious).  But that doesn't matter since
    we're computing both solutions anyhow.
    
    And I agree that the equations should be perfectly well behaved in all
    practical cases.  They only blow up at 90d declinations, 90d
    altitudes, or zero D12 -- cases that will never occur in practice.
    Also the equations will give the correct result for osculating LOPs.
    In that case B=0, and the two solution for (A+B) and (A-B) will give
    the same answer.
    
    So these equations should be straight forward to implement in computer
    code.
    
    John
    --~--~---------~--~----~------------~-------~--~----~
    NavList message boards: www.fer3.com/arc
    Or post by email to: NavList@fer3.com
    To unsubscribe, email NavList+unsubscribe@fer3.com
    -~----------~----~----~----~------~----~------~--~---
    
    

       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Join NavList

    Name:
    (please, no nicknames or handles)
    Email:
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.
    Email:

    Email Settings

    Posting Code:

    Custom Index

    Subject:
    Author:
    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site