NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Another "emergency navigation" sight reductionmethod
From: Hanno Ix
Date: 2015 Jul 17, 03:44 -0700
Therefore, the table entries decrease by 0.14 for this 10' step or by 0.014 for a 1' step
I believe we are beyond the max return for the effort - an effort that has to be
repeated for each SR. Personally, I'd stay with the old 4 digit 2 ' steps format.
From: Hanno Ix
Date: 2015 Jul 17, 03:44 -0700
Greg,
here is an attempt of wording the interpolation procedure to be included on the table.The space on the table page can be accommodated.
Example of interpolation: Finding the value of 40° 22'
Find on the table at 40° 20' the entry 18.89, and at 40° 30' the entry 18.75.Therefore, the table entries decrease by 0.14 for this 10' step or by 0.014 for a 1' step
which means a decrease by 2*0.014, or ~ 0.03, for the 2' step from 40° 20' to 40° 22'.
So the desired value for 40° 22' is 18.89 - 0.03 or 18.86.
So the desired value for 40° 22' is 18.89 - 0.03 or 18.86.
Note: The USN determined that reading the table entries as if they were $ amounts
increases accuracy of reading, retention and mental calculations. Ex: read 18.86 as $18.86.
increases accuracy of reading, retention and mental calculations. Ex: read 18.86 as $18.86.
Too long! Could not find any better.
I do not want to rain on your party: Compressing the tables from 2 pages to 1 page
necessitates an error prone interpolation and also 5 digit numbers which
complicates the process not insignificantly and makes it more error prone.
necessitates an error prone interpolation and also 5 digit numbers which
complicates the process not insignificantly and makes it more error prone.
All this for just a single page table reduction?
I believe we are beyond the max return for the effort - an effort that has to be
repeated for each SR. Personally, I'd stay with the old 4 digit 2 ' steps format.
I will send you a xxxxx table anyway.
H
On Thu, Jul 16, 2015 at 8:06 PM, Greg Rudzinski <NoReply_Rudzinski@navlist.net> wrote:
Robert,
The decimal placed in the log sin is just a mark for interpolation convenience ( xxx.xx = xxxxx ). {at} Hanno, better go to the xxxxx version otherwise there will be confusion.
Greg Rudzinski
From: Robert VanderPol II
Date: 2015 Jul 16, 19:09 -0700"18.89 - 3 (rounding 2.8 to 3) = 18.86"
I don't think so.
