Can you finish the Mathcad 15 sheet in attach?

[ValeryOchkov]

I would like to create the web-sheet for calculation S and L between two place on Earth with geo coordinate.

Finish please the sheet in attach!

[MJG]

I think you'll find the information you need here: https://en.wikipedia.org/wiki/Great-circle_distance#Formulas

[ValeryOchkov]

Thanks, Mark.

It is a subproblem for this problem - http://twt.mpei.ac.ru/ochkov/SPB-Moscow-Train.pdf

There is one online calculator Online calculator: Course angles and distance between the two point on the orthodrome(great circle)

But my dada is open web online calculations with Mathcad (MAS and MCS) with view all formulas and Intermediate results.

[-MFra-]

Hello Valery Ochkov!

Do you think, my reply is satisfactory?

Let me know, so also will attach the worksheet.

Greetings Franc.

[ValeryOchkov]

Thanks, Franc.

See please the solution from my students.

http://twt.mpei.ac.ru/MCS/Worksheets/Earth-D-L.xmcd

Is it correct?

-Val

[ValeryOchkov]

First question.

What kind of animal is that?

It's green, it lives at a depth of 2 m and feeds on stones!

The answer - a green stoneeater.

Second question.

What happens if through the center of the Earth to dig a tunnel and throw a stone in the tunnel?

The answer is - a green stoneeater will eat this stone at a depth of 2 meters.

[-MFra-]

Excuse me, I'm a retired teacher from 2011. Of the students I have balls full ... so, please do not talk about students ...

Will be for another time.

Greetings Franc.

[ValeryOchkov]

F.M. написал(а):

Excuse me, I'm a retired teacher from 2011. Of the students I have balls full ... so, please do not talk about students ...

Will be for another time.

Greetings Franc.

Sorry - is the calculations wrong?

[-MFra-]

I see that the results are different from mine. Maybe there are different data.

(indeed there is something wrong in the data. I do not know the Russian language.)

Deactivating the definition in degrees of latitude and longitude and measuring them in radians, I get:

[Werner_E]

I maybe wrong and maybe I am missing the point, but isn't this a fairly easy task?

Using just those three formulas:

I can't check your students sheet as its not available anymore, but for the distance on the orthodrome at least I get the very same result as the site you try to duplicate.

To perfectly duplicate the values this site gives back when you choose "ball" you have to set the earth radius to 6378.137 km as this seems to be the value used at that site. Its not the mean value usually taken to make a sphere the same volume as the geoid but this value is the radius at the equator according to the ellipsoid GRS 80 resp. WGS84 from the year 1979.

In the map below I also draw the orthodrome of the two points, the great circle they are lying on. Of course it does not appear as a straight line in the Mercator map.

Regards, Werner

[-MFra-]

Sorry to return again on the subject. I want to clarify that the angles by me used (latitude and longitude) are those commonly used in analysis, geometry and electromagnetism and illustrated in octant here depicted below. Certainly I have not referred to the conventions of the art navigation or similar. (The z axis coincides with the terrestrial axis.)

Bye

[Werner_E]

You didn't use geographical coordinates as needed, so this explains the wrong results you got.

It furthermore explains your confusion about the North-South, East-West selectors, which you unfortunately had disabled in your last version. I don't know any Russian at either all but the meaning was clear from the context if you think of geographical coordinates - those selectors had to be there (and they are, too, on the site, Valery had  linked to and which he is trying to imitate) . They do not do any harm - they just change the sign if needed (if South or West is selected) and have nothing to do with degree vs. radian. Valery just displayed the results in degrees (which makes much sense in this context).

So I guess your picture of the earth is just a static one and is not dynamically showing the entered locations as the Mercator plot does finally (this was the main work and its still unsatisfactory).

I was not able to find a decent set of continent border data to make a 3D earth plot showing the locations and connections. Maybe some day when I am really bored I'll download a set of KML data and extract the coordinates - but then, probably not.

Werner

[-MFra-]

Thank you, Werner for your kind response. Certainly, I have considered the angles in radians, already present in the worksheet of Valery. My graphics, no claim, they are sketches made with Paint. The verification of the measurement of distances can be done with "Google Earth", I'm sure you certainly know (here, in my country, it is very common) and from which I have drawn the image of the globe with a simple  keyboard print. What I mind is the correctness of the calculations resulting from geometrical considerations in space. Not knowing the Russian language, I tried to translate with google translator the fundamental astronomical four directions north south east west, associated with the radio button, but I did not find the correspondence, even with abbreviations. I had guessed, but I preferred to proceed. The answers that I generally do, are the proofs that need, as such, more and corrections. But I think that, since it's only recently that I try to participate in discussions it happens that, as you know, when something starts, the output can have a transitory with "ups and downs" dangerous, which then dampen. It would not be wise, for me, to continue down this road.

Merry Christmas

With best regards

F. M.

[Werner_E]

I used Google translator, too, and also could not find those abbreviations 😉 But it had to be the directions as it deals with geographical coordinates (and of course I looked at the calculation page Valery referred to. Shame on Valery for not providing an English sheet.

But I think that, since it's only recently that I try to participate in discussions it happens that, as you know, when something starts, the output can have a transitory with "ups and downs" dangerous, which then dampen. It would not be wise, for me, to continue down this road

I think I don't understand the meaning of those lines!?

All the best to you, too

Werner

[ValeryOchkov]

Werner Exinger написал(а):

...East-West selector...

Werner

The Greenwich meridian Prime meridian - Wikipedia, the free encyclopedia

(Foots and photo by Valery Ochkov)

[-MFra-]

Read: not octant but hemisphere.