Facebook

Login

Support Sailonline

If you haven't already - join the SAILONLINE YACHT CLUB!

Please also consider making a donation - all amounts are greatly appreciated!

Board » General Discussion » Race ranking

Page: 1 2 3 Next

Posted by
Incognito


Users avatar

Posts
183
Registered at
2008-12-06 13:43:52
2009-05-22 07:20:35 - Race ranking
Hi SOLer's,

I think the topic has already been raised in the past. In leg 7, I notice that SOL's race ranking are looking strange

According to SOL, at 7:00 UCT, I was ranked 86th with more than 674 NM to go.

In brainaid's ranking however (http://sol.brainaid.de/pub/ranking-145.html), I was ranked 14th with 637 NM to go.

Quite a difference! And when I use the pliers or the pointer to calculate the DTG, I come to a figure similar to brainaid's.

Personnally, I remain convinced that SOL's ranking is not working properly. It would be nice to fix that.

Regards,

Francois
Posted by
jakob


Users avatar

Posts
364
Registered at
2007-09-04 10:05:30
2009-05-22 07:41:10 - Re: Race ranking
Different DTG-calculation routines apply with varying success in different situations. The SOL-scheme is designed to work fairly ok at all situations and requires little cpu. I do not know much about the Brainaid calcs. He has access to our code though so maybe he will help us with a new system ;-). Having said that, to be 6% off when there is over 600nm to go is maybe something we can live with. In the end the two systems converge, I promise.
...one of the guys behind the game...
Posted by
Incognito


Users avatar

Posts
183
Registered at
2008-12-06 13:43:52
2009-05-22 08:19:44 - Re: Race ranking
Yes, Jakob, I know that both rankings will converge. :-)

Nevertheless, the differences are
very substantial in fact. More importantly, the SOL ranking presents a misleading picture of the race.

What I do not understand is that you were able to program broadly correct formulas for the pliers and for the mouse pointer, but not for the rankings.

Regards,

Francois
Posted by
skantorp


Users avatar

Posts
2
Registered at
2008-06-26 11:21:09
2009-05-22 08:46:39 - Re: Race ranking
seems to me that the sol ranking is based on a straight line to finish wheras brain is using the great circle to calculate distance and rank... might be wrong though...
Life is a holiday under the sun
Posted by
JuJu


Users avatar

Posts
24
Registered at
2008-12-24 09:50:12
2009-05-22 09:08:34 - Re: Race ranking
I'm guess that the pliers and mouse pointers are in the client (flash) code and the rankings are running on the database server where SQL doesn't make it easy/fast to do a great circle calculation (guess they don't have Oracle with the GEO option).
Posted by
jakob


Users avatar

Posts
364
Registered at
2007-09-04 10:05:30
2009-05-22 10:16:26 - Re: Race ranking
I am starting to learn that Skan is seldom wrong :-) I will check. hold... Checked and Skan was right!! I used the rhumb-line. Now switched to great circle. BUT there will still be difficult occasions when there are intermediate waypoints... so the discussion will continue I bet. Thanks for caríng all!!
...one of the guys behind the game...
Posted by
Incognito


Users avatar

Posts
183
Registered at
2008-12-06 13:43:52
2009-05-22 15:39:45 - Re: Race ranking
Thanks Jakob. When is it going to be implemented?
Posted by
jakob


Users avatar

Posts
364
Registered at
2007-09-04 10:05:30
2009-05-22 18:15:19 - Re: Race ranking
It is implemented. :-)
...one of the guys behind the game...
Posted by
captjack1942


Users avatar

Posts
239
Registered at
2008-01-18 03:24:03
2009-05-22 23:46:05 - Re: Race ranking
How about some more head spinning observations?
@23:06 UTC for captjack1942:

SOL) #186 ; 481.6 mi to go.

Brain's ranking page) #109 ; 389.4 mi to go.

Ed Williams' great circle calculator (http://williams.best.vwh.net/gccalc.htm); 386.49 mi to go.


For the calcs: CJ1942 position @ 23:06 --- 54.52 N / 19.73 W.
Pin on Aran Is--- 53.15 N / 09.79 W.
Center of finish line off Galway --- 53.20 N / 09.12 W.
Earth model WGS84/NAD83/GRS80.

Also note that brain's position was updated @ 23:00. At 22.3 kts for 6 min =2.23 mi.

;-)
Posted by
Incognito


Users avatar

Posts
183
Registered at
2008-12-06 13:43:52
2009-05-23 06:40:35 - Re: Race ranking
Jakob, I do not want to pest you, but there are still very large differences between DTG in ranking and as measured. For my boat right now: 267 NM vs 190 NM. That does not seem normal to me.

May I perhaps suggest that you check the coordinates of the waypoint used for the rankings? Or is it automatically linked to what is shown on the screen? For a sample of boats, I notice that the DTGs would be consistent with a waypoint slightly east of the Fastnet Rock.

Page: 1 2 3 Next

Please login to post a reply.

Races

Next Race: 00d 00h 00m

Current Races:

Aeolian Cruise 2025


This is the final race of the ARCH 2025 series and your last chance to improve your ranking. It promises to be an exciting 210nm slalom through the beautiful landscapes of the Aeolian Islands. Our Moody S38's will take off from Tropea and sail west between successive islands to reach the finish line in the Gulf of Palermo.
Fair Winds.
Race #1991
INFO from brainaid.de
Moody S38 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
ARQ4 - ARCH - SUPSOL - SYC
Race starts: Dec 15th 17:00 Registration Open!
▶ Flash
GO TO RACE

Chatham Island TIMED Chase 2025

The final TIMED race of 2025 takes us to the isolated and mysterious Chatham Islands archipelago 430 nm east of New Zealand’s South Island. There promises to be plenty of breeze from every point on the compass as we sail the Farr 38 around Chatham Island, Pitt Island, and The Forty Fours on this 124 nm course. This is a TIMEDrace so you may RE-REGISTER HEREto try again after finishing a run. You will have 13 days and 11 hours to test your skill and decision making after the race opens.
Race #1990
INFOby brainaid.de
Farr 38 Particulars
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
TRQ4 - TRCH - SUPSOL - SYC
RACE CLOSE: Saturday,
27 December at 23:00 UTC
Race starts: Dec 14th 12:00 Registration will open soon
▶ Flash
GO TO RACE

Christmas to Christmas Island 2025

Two waypoints, start and finish, and between them 5827 NM of two oceans. Not much time if we want to sit at the Christmas Eve table. You will need to maintain an average speed of over 10 knots, maybe quite possible with this Maxi Trimaran, but prepare your vessel well and choose the best of the many possible routes. Hands up everyone who knew there were TWO Christmas Islands?! OK, maybe you have sailed this Sailonline course before... but it's time to get ready for the 2025 challenge of racing between Christmas Island in the Pacific to Christmas Island in the Indian Ocean! It also marks the conclusion of our prestigious Ocean Race Championship 2025. Please have fun! Fair winds!
PRIZE: SMPF
Race #1967
INFO by brainaid.de
Maxi Trimaran PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: OCQ4 - OCCH - SUPSOL - SYC
Race starts: Dec 01st 11:00 Registration Closed
▶ Flash
GO TO RACE

Go to race archive

SYC Ranking

  1. Sailonline Yacht Club Member KaSToR
  2. Sailonline Yacht Club Member CriticalHippo
  3. Sailonline Yacht Club Member WRmirekd
  4. Sailonline Yacht Club Member rafa
  5. Sailonline Yacht Club Member vida
  6. Sailonline Yacht Club Member CollegeFund
  7. Sailonline Yacht Club Member bonknhoot
  8. Sailonline Yacht Club Member Panpyc
  9. Sailonline Yacht Club Member sassy63
  10. Sailonline Yacht Club Member BRENTGRAY

View full list

Series

Mobile Client

SYC members have the benefit of access to our mobile/lightweight web client!

The mobile client