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Plot an expression along a specific coordinate system
Posted 15.01.2013, 06:39 GMT-5 Version 4.3a 1 Reply
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Hi
I defined a cylindrical system (r,phi,a) and I'd like to get the results along one of these specific coordinates.
Since all the direct results expressions are defined in cartesian coordinates (x,y,z). I would like my magnetic field along x "mf.Hx", as an example, to be expressed and shown along r.
I found that the way to do so seem to insert an expression in the plot expression setting. I found that the cylindrical system is included in the definitions window. But I can't find a way to have my expression calculated along r since I get an error. Also, I can't figure out which one to select from the list between "Base vector (sys2) a", "coordinate, a component (sys2.a)" or "coordinate transform to system (sys2)".
What should I do please ?
Thanks a lot
I defined a cylindrical system (r,phi,a) and I'd like to get the results along one of these specific coordinates.
Since all the direct results expressions are defined in cartesian coordinates (x,y,z). I would like my magnetic field along x "mf.Hx", as an example, to be expressed and shown along r.
I found that the way to do so seem to insert an expression in the plot expression setting. I found that the cylindrical system is included in the definitions window. But I can't find a way to have my expression calculated along r since I get an error. Also, I can't figure out which one to select from the list between "Base vector (sys2) a", "coordinate, a component (sys2.a)" or "coordinate transform to system (sys2)".
What should I do please ?
Thanks a lot
1 Reply Last Post 15.01.2013, 08:01 GMT-5
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Posted:
1 decade ago
Hi
the cylindrical coordinates "sys2" (or 3 or 4 depending on how many you define) defines (sys2.r sys2.phi sys2.a) with something like a=z-Z0 r=sqrt((x-X0)^2+(y-Y0)^2) and phi=atan2((y-Y0),(x-X0) (pls check I might have got a sign wrong ;) with (X0,Y0,Z0) the origine of your
Still you need two write out your results fully with cylindrical coordinates in a similar way
You have also the coordinate transform matrix values sys2... as well as the inverse, check the Results tab and the doc for the full naming convention
--
Good luck
Ivar
the cylindrical coordinates "sys2" (or 3 or 4 depending on how many you define) defines (sys2.r sys2.phi sys2.a) with something like a=z-Z0 r=sqrt((x-X0)^2+(y-Y0)^2) and phi=atan2((y-Y0),(x-X0) (pls check I might have got a sign wrong ;) with (X0,Y0,Z0) the origine of your
Still you need two write out your results fully with cylindrical coordinates in a similar way
You have also the coordinate transform matrix values sys2... as well as the inverse, check the Results tab and the doc for the full naming convention
--
Good luck
Ivar