The Ocean Race 2023 leg 3: Capetown to Itajaí, Brazil

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noaano

Anarchist
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Panoramix said:
all this to sum 2 vectors...
sqrt( (boat_speed+ TWS * cos(TWD) )^2 + (TWS * sin(TWD) ) ^2 )
Click to expand...

Correct answer is always to use numpy, I assume? :)

You find all sorts of funny things in the code generated.

Sometimes even blatant mistakes, try putting it to do any RF or DSP stuff and it gets it often totally horribly wrong.

I think this will not make us jobless, but it raises the bar for sure.
 
dg_sailingfan

dg_sailingfan

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Herman said:
MAPFRE got rolled drifting for hours under the Table mountain by Team SCA, although the ladies were way way way behind them.

I did not remember that Nico was the navigator. He was not crew on the next leg.
Click to expand...
Yeah, Iker Martinez saw what a clusterfuck he did by chosing Nico and changed him out for Jean-Luc Nelias for the rest of the Race on Mapfre.

Lunven is a bad Navigator. Malizia not winning Leg 2 when they had a chance to do it was entirely his fault. Had they stuck to the other 3 Boats in the north they might have had a better Result than fourth which might have in hindsight changed this whole TOR Edition around for them.
 
H

Herman

Super Anarchist
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The Netherlands
So it begins. With Team Malizia doing 65 km/hour during a gust. I try to visualize that.

1680274597211.png
 
N

noaano

Anarchist
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Hard to pick my favorite from these absolute gems:

Code: 
The Tragedy of Apparent Wind Speed

Act I: Scene I

[Enter True Wind Angle, True Wind Speed, and Boat Speed]

True Wind Angle:
Am I the angle from which the true wind blows?
True Wind Speed:
Am I the speed of the true wind, in knots?
Boat Speed:
Am I the speed of the boat, in knots?

[Exit True Wind Angle, True Wind Speed, and Boat Speed]

Act I: Scene II

[Enter Knots to Meters Per Second]

Knots to Meters Per Second:
Art thou the factor by which to convert knots to meters per second?

[Exit Knots to Meters Per Second]

Act I: Scene III

[True Wind Angle crosses stage left. True Wind Speed crosses stage left. Knots to Meters Per Second crosses stage left.]

[Enter Angle in Radians, Apparent Wind Speed, and Apparent Wind Angle]

Angle in Radians:
Art thou the angle in radians of the true wind?
Apparent Wind Speed:
Art thou the speed of the apparent wind, in meters per second?
Apparent Wind Angle:
Art thou the angle from which the apparent wind blows?

[Exit Angle in Radians, Apparent Wind Speed, and Apparent Wind Angle]

Act I: Scene IV

[Boat Speed crosses stage left.]

[Enter Apparent Wind Speed Squared]

Apparent Wind Speed Squared:
Art thou the square of the speed of the apparent wind, in meters per second?

[Exit Apparent Wind Speed Squared]

Act I: Scene V

[Boat Speed crosses stage left. True Wind Speed crosses stage left.]

[Enter True Wind Speed Squared, Boat Speed Squared, and Two Times True Wind Speed Times Boat Speed Times Cosine of Angle]

True Wind Speed Squared:
Art thou the square of the speed of the true wind, in meters per second?
Boat Speed Squared:
Art thou the square of the speed of the boat, in meters per second?
Two Times True Wind Speed Times Boat Speed Times Cosine of Angle:
Art thou twice the product of the true wind speed and the boat speed, multiplied by the cosine of the angle?

[Exit True Wind Speed Squared, Boat Speed Squared, and Two Times True Wind Speed Times Boat Speed Times Cosine of Angle]

Act I: Scene VI

[Enter Apparent Wind Speed]

Apparent Wind Speed:
You are the square root of the sum of the true wind speed squared, the boat speed squared, and twice the product of the true wind speed and the boat speed, multiplied by the cosine of the angle, all divided by the knots to meters per second factor.

[Exit Apparent Wind Speed]

Act I: Scene VII

[Enter Apparent Wind Angle]

Apparent Wind Angle:
You are the arctangent of the quotient of the sum of the true wind speed and the boat speed, multiplied by the sine of the angle, and the cosine of the angle, all converted to degrees.

[Exit Apparent Wind Angle]

Act I: Scene VIII

[Exeunt]

The End.

Code: 
True wind angle: 45 degrees
True wind speed: 15 knots
Boat speed: 10 knots

Ingredients.
1 angle (degrees) = 45
1 true_wind_speed (knots) = 15
1 boat_speed (knots) = 10
1 knots_to_mps = 0.51444

Method.
Combine the angle and the knots_to_mps and let it rest.
Combine the true_wind_speed and the knots_to_mps and let it rest.
Combine the boat_speed and the knots_to_mps and let it rest.
Multiply the angle by pi.
Divide the angle by 180.
Multiply the true_wind_speed by the sin of the angle.
Multiply the boat_speed by the knots_to_mps.
Add the true_wind_speed and the boat_speed.
Multiply the true_wind_speed by the cos of the angle.
Add the previous result to the current result.
Divide the previous result by the previous result.
Take the arctangent of the previous result.
Let the result rest.
Combine the boat_speed and the knots_to_mps and let it rest.
Raise the previous result to the power of 2.
Combine the true_wind_speed and the knots_to_mps and let it rest.
Raise the previous result to the power of 2.
Add the previous two results.
Combine the boat_speed and the true_wind_speed and the knots_to_mps and let it rest.
Multiply the previous three results together.
Multiply the previous result by the cos of the angle.
Subtract the previous result from the previous result.
Take the square root of the previous result.
Divide the previous result by the knots_to_mps.
Let the result rest.

Serve with a side of wind speed and wind angle.

Wind speed: 12.24 knots
Wind angle: 30.95 degrees

Code: 
HOW TO CALCULATE APPARENT WIND SPEED WITH TRUE WIND ANGLE, TRUE WIND SPEED, AND BOAT SPEED:

HAI 1.3

VISIBLE "Enter True Wind Angle, True Wind Speed, and Boat Speed"
GIMMEH true_wind_angle
GIMMEH true_wind_speed
GIMMEH boat_speed

VISIBLE "Enter Knots to Meters Per Second"
GIMMEH knots_to_mps

VISIBLE "Calculating Apparent Wind Speed and Apparent Wind Angle..."

I HAS A angle_in_radians
angle_in_radians R IT true_wind_angle * PI / 180

I HAS A apparent_wind_speed_squared
apparent_wind_speed_squared R IT true_wind_speed^2 + boat_speed^2 - 2 * true_wind_speed * boat_speed * COS(angle_in_radians)

I HAS A apparent_wind_speed
apparent_wind_speed R IT SQRT(apparent_wind_speed_squared) / knots_to_mps

I HAS A sin_angle
sin_angle R IT SIN(angle_in_radians)

I HAS A cos_angle
cos_angle R IT COS(angle_in_radians)

I HAS A apparent_wind_angle
apparent_wind_angle R IT ATAN((true_wind_speed * sin_angle) / (boat_speed + true_wind_speed * cos_angle)) * 180 / PI

VISIBLE "The Apparent Wind Speed is " SMOOSH apparent_wind_speed " m/s."
VISIBLE "The Apparent Wind Angle is " SMOOSH apparent_wind_angle " degrees."

KTHXBYE

Bonus point to anyone recognizing the languages used.

And yes, these are actual programs in an actual, if a bit unusual language.
 
Last edited:
N

noaano

Anarchist
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Panoramix said:
Sometimes but not always, my old HP48 is still functioning and regularly beat the young ones because it takes time to open a spreadsheet and less than 2 seconds to put an old HP in action.
Click to expand...

BTW, I still use a HP48 emulator on my iPad if not daily, then at least weekly.

Only when I need the one and only ALG48 will I get the real HW - I have not managed to get that run properly in an emulator - usually to find the batteries are flat from years of storage :)
 
dg_sailingfan

dg_sailingfan

Super Anarchist
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996
Augsburg
As you can see here MALIZIA bore off slightly to the east
Opera Momentaufnahme_2023-03-31_171336_team-malizia.geovoile.com.png

I still feel that we are potentially close to a breakdown or dismasting in these kind of conditions.
Groupama got dismasted around the same area in 2012 and eventually needed to head to Punta del Este to install a Jury Rig!

I hope both boats get through this without a Major bustard.
 
TheDragon

TheDragon

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East central Illinois
dg_sailingfan said:
As you can see here MALIZIA bore off slightly to the east
View attachment 583117
I still feel that we are potentially close to a breakdown or dismasting in these kind of conditions.
Groupama got dismasted around the same area in 2012 and eventually needed to head to Punta del Este to install a Jury Rig!

I hope both boats get through this without a Major bustard.
Click to expand...
oops, malizia way slow and ddw, something wrong here.
 
Rennmaus

Rennmaus

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2 interviews:
Guyot environnement - Team Europe (FRA/ GER)
Benjamin Dutreux (FRA) - Skipper - Interview in ENGLISH
Benjamin Dutreux (FRA) - Skipper - Interview in FRENCH

 
P

Panoramix

Super Anarchist
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Rennes, Brittany, France
noaano said:
BTW, I still use a HP48 emulator on my iPad if not daily, then at least weekly.

Only when I need the one and only ALG48 will I get the real HW - I have not managed to get that run properly in an emulator - usually to find the batteries are flat from years of storage :)
Click to expand...
I am not sophisticated enough to need an algebra system (just a structural engineer!) but I like so much the reverse polish notation and the clicky keys... so until it dies, anybody who wants it will have to pry it out of my cold dead hands. I bought it in 1994, I am amazed that it is still going.
 
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