Re: About Vector plot

From: David Brown <dbrown_at_nyahnyahspammersnyahnyah>
Date: Tue May 10 2011 - 17:54:39 MDT

By default, the vector direction is mapped into the coordinate space defined by the coordinate variables. This is appropriate for horizontal vectors drawn on a map, but not for vectors in a vertical space such as yours where the Y axis and the X Axis have completely unrelated units. To fix this you should set the resource vcMapDirection to False. This will make the output of gsn_vector and
gsn_csm_vector look pretty much alike. However, it also has the effect of always making the positive Y direction from bottom to top. If, as you say, the gsn_vector output looks like what you want, it may mean the vertical component is positive from top to bottom of the atmosphere. If this is the case, then you will need to multiply the vertical component by -1.0 to get the result you are looking for.
Hope this helps.

On May 6, 2011, at 3:39 AM, Cheung wrote:

> Dear all:
> I have a 2d data plotted respectively by gsn_vector and gsn_csm_vector, but the results are different. (attached files)
> And the 'gsn_vector' one is reasonable cause I also use other software to display the data. So can anyone tell me why, I really
> need to use gsn_csm_vector because of some functions. My data is u(lev, lon) and w(lev,lon) , 22*25. no special resources set.
> Regards!
> <gsn_csm_vector.png><gsn_vector.png>_______________________________________________
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Received on Tue May 10 17:54:53 2011

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