North in SunPtah component takes number incorrectly - vector correctly

[zati89]

Maybe other components using the same rotation code are also affected. The rotation (north), is taken incorrectly when just a number slider are conected, from a vector (true North component) is taken correctly - I double checked it with manual rotation and also the view from the sun

[mostaphaRoudsari]

@devngc, is it something that you might be interested to check?

@zati89, so you are saying the true-north-vector is also exactly 41 degrees from the north?

[devang-chauhan]

@mostaphaRoudsari, Yes. Absolutely.

[zati89]

@mostaphaRoudsari - honestly I don't know about the vector to be honest, but the north arrow components is correct

[devang-chauhan]

I will get back to you.

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@mostaphaRoudsari https://github.com/mostaphaRoudsari - honestly I don't know about the vector to be honest, but the north arrow components is correct

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[devang-chauhan]

@zati89, The true north component is provided to derive true north from the magnetic north that you might get from the compass app on your phone or in some cases, magnetic north is mentioned on the site layouts rather than the true north.

Therefore, by using google maps, you can find the true north for any location pretty easily. And that true north shall be used for all solar studies.

Considering that, attaching a number to indicate true north is fine. In the image above, I am using the magnetic declination for Toronto to find True north (Which I already know from google maps). In this case, the output of the true north component and the sunpath diagram are aligned.

Please share if I missed something here. The file can be found here

[zati89]

Hi @devngc ,

thats clear, my point is, When I input the vector I get a different result from that if I input a number to reffer to norh. You can double check it if you rotate a model manualy, and rotate just with an input number + watch it with the view from the sun. @mostaphaRoudsari can you please forward to devang my files I sent to you, I have them on different computer so can't do it now

[devang-chauhan]

@zati89 , Can you please share the files?

[mostaphaRoudsari]

Shared!

[devang-chauhan]

@zati89, Mostapha shared with me your files. Can you also share the location of this building / proposed building on google maps?

[devang-chauhan]

In the first image below, text input is provided to the north input of the sunpath In the second image below, we use the north vector from the true north component You can see that there's major difference in the North direction.

when you are supplying a number to the north input it is assumed that you already know what True north is for the building. Which is mostly the case thanks to Google maps. If you plug that number to the true north component then you should expect a very different results.

[zati89]

Hi @devngc ,

Yes this is the behavior I saw, but I was expecting to have the same result, why is the result from the true north components vector so much different ? Does it makes sense ?