World Magnetic Model Plugin

[nohal]

Originally Posted by Gilletarom

No, not stable because the window is above all other windows and this is unpleasant

can't reproduce - the window is above opencpn's window all the time, same as for example the grib plugin's one. This is intended.

What are the units for F, H, X, Y, Z, Incl, Decl ? Is it possible to write these units in each line ?

F, H, X, Y, Z - unit is nT - nano Tesla
Inclination and Variation - degrees
There is no "Decl" and the units are shown in all the fields in 0.2 - are you really using this new version?

It would be nice if there was a button on the "Boat" of the extended display. This button would go to shows simplified and vice-versa.

I want to keep the window as small as possible, that's why there's no button.

logfile is .log - the plugin writes a message in the logfile if the WMM.COF file is not found and it uses the bundled data. For the time beeing not having that file is ok, for the next epoch, you can use the new one when it's released by NOAA.

Pavel

[Gilletarom]

Hello Pavel

1° I made ​​a translation of the "pot" with poedit.

I made ​​an "po." I call it "openCPN-WMM_pi.po" and automatically a 'mo'.
I put these txo files in the correct folder of the software.

This allowed me to try the French version.

I noticed it was missing an item in the "pot". This is the item "Declination only" (but there is "Variation only" which is useless). See the attached file.

2° On the window of the plug-in, there is at left of the title, a buton. If clicked, we are given two options:
Close and move.

But to close, there is the red cross and to move, just take the window with the mouse.

In my opinion, this button is useless.

Best regards

Gilletarom

[nohal]

Gilletarom,
send me what you have, I will add "Seulement variation" myself when I figure out why there is a problem.
Interesting thing that icon, I don't have it here...

Pavel

[Gilletarom]

Hello

Originally Posted by Gilletarom

Hello Pavel

1° ......

2° ......

Oops ... I'm sorry ... I continued to work with version 0.1 by mistake. But without crash !!!! Strange.

Now I have change for the .02.

And the problems I reported were already solved ...

I apologize again.

Here I join the .po that I have created for French version.

Gilletarom.

[NAV]

Pavel,
Attached are the Dutch language files for the WMm plugin.

[nohal]

Thanks guys, all available at https://github.com/nohal/OpenCPN/downloads

Pavel

[NAV]

In the OpenCPN manual Andres has changed a part of my text on the page Supplementary Software/Magnetic Variation, and added: "(historically called in navigation domain: magnetic declination. Magnetic variation is the physic term)".

I don't mind the change, but don't agree. Attached are two pages from two ancient navigation textbooks: " 'T Vergulde Licht Der Zeevaard" (by Klaas Hendriksz. Gietermaker, 1774, in Dutch) and "The New Practical Navigator" (by John Hamilton Moore, 1807, in English, being the text on which the original Bowditch was based). Both use the word "variation", not "declination". In my opinion "declination" is the physical term.

[NAV]

;-) And even more historical this page of "Tweevoudigh Onderwiis van de Hemelsche en Aerdsche Globen" ("Twofold Education of Heavenly and Earthly Globes", 1655, Willem Jansz. Blaeu, in Dutch).

[nohal]

My dutch begins and ends with "egel in da kooi" and even that is probably wrong , but the other sources in languages I actually understand say variation is the term we should use while navigating. I actually care much more about the numeric value I have to add or substract to get the magnetic course to steer than how it's called. My very internal feeling is we probably should send a beer to the declination lovers who actually gave us the formulas and data to compute it
Anyway, variation is going to be the term this plugin is going to use "officially".

Pavel

[NAV]

I agree to sending the beer! No doubt on my side about what physicians, then and now, have done for us.

At the same time I think it's wise not to confuse starting sailors.

Anyway, this discussion is slightly off topic (although it nicely brings together old and new).

[Andres_RG]

I have read today the polemic about variation vs. declination. It was not my intention to create it, (the butterfly effect).
I think it is also a language issue.

In this old manual of navigation refers it as "declinación magnética de la brújula": Breve compendio de la sphera y de la arte de navegar. Martín Cortés de Albacar. Sevilla 1551, London 1561.

Also spanish paper nautical charts called it "declinación magnética"
I have updated the Magnetic Variation | Official OpenCPN Homepage

Beers for all

[NAV]

Hmmm ...
It's not very likely that I will find an older publication than you did, Andres.

[sailorF54]

In France / French, variation W is the algebric sum of (magnetic) declination D and deviation d (due to iron masses on the boat) (French Navy...)

However, variation was widely used instead of declination in the XVIIIth century

[NAV]

Looks like it is a difference between Germanic and Romance languages.

For those interested in history, following is a publication (1961, in English) about Simon Stevin's work on Astronomy and Navigation: http://www.library.tudelft.nl/tresor...my-Navigation/

The original text of the part "Havenvinding" (1599, in Dutch): http://www.library.tudelft.nl/tresor...edachtenissen/

[sailorF54]

"The earliest known reference to the existence and influence of magnetic declination on navigation is generally attributed to Columbus, during his first voyage to the West Indies, in 1492, who reported having observed a ‘true meridian’ (meridiano vero), where the magnetic declination was zero, near the Azores archipelago. Also, the name given to Cape Agulhas in the Cantino planisphere – Cabo das Agulhas (‘Cape of the Needles’) – is an indication that the magnetic declination in the area was close to
zero at the time and that the phenomenon was observed and registered during some exploratory mission that preceded the making of the chart13. The Portuguese pilots used the verbs nordestear (to point ‘eastward’) and noroestar (to point ‘westward’) to express the tendency of the magnetic needles to point to the east or to the west of the geographic North."
(page 18)

Note 13
This was confirmed by D. João de Castro (1500-1548), who made the earliest known systematic measurements of the magnetic declination during his trip from Lisbon to India, in 1538. In the Roteiro de Lisboa a Goa (‘Rutter from Lisbon to Goa’), on 5 July 1538, he writes: ‘this Cabo das Agulhas is the place where the pilots have the precept that their needles don’t show any variation’ (este Cabo das Agulhas é o lugar onde os pilotos têm por maxima que as suas agulhas não variam coisa alguma). See Castro (1538).

FROM THE PORTOLAN CHART OF THE MEDITERRANEAN TO THE LATITUDE CHART OF THE ATLANTIC - CARTOMETRIC ANALYSIS AND MODELING
Joaquim Filipe Figueiredo Alves Gaspar

PhD Universidade Nova de Lisboa 2010
http://www.ciuhct.com/online/docs/th...ar_2010-v2.pdf