From debasish.hazra5 at gmail.com Tue Sep 12 12:58:23 2023 From: debasish.hazra5 at gmail.com (Debasish Hazra) Date: Tue, 12 Sep 2023 14:58:23 -0400 Subject: [ncl-talk] wind plot Message-ID: Hi, I have calculated wind speed and direction using wind_Stat function in NCL. While plotting, I can use gsn_csm_contour_map_ce to plot wind speed but how do I overlay wind direction on it using gsn_vector plot, as it needs both u and v in the resource. Is there any example available on how to plot wind speed and direction together ? Thanks Debasish -------------- next part -------------- An HTML attachment was scrubbed... URL: From dave.allured at noaa.gov Tue Sep 12 14:13:34 2023 From: dave.allured at noaa.gov (Dave Allured - NOAA Affiliate) Date: Tue, 12 Sep 2023 14:13:34 -0600 Subject: [ncl-talk] wind plot In-Reply-To: References: Message-ID: NCL has special functions which combine contours and vectors into a single function call. Go to this page which links off from NCL Examples: https://www.ncl.ucar.edu/Applications/func_list.shtml Then search for "vector_scalar_map". There are several examples. On Tue, Sep 12, 2023 at 12:58?PM Debasish Hazra via ncl-talk < ncl-talk at mailman.ucar.edu> wrote: > Hi, > I have calculated wind speed and direction using wind_Stat function in > NCL. While plotting, I can use gsn_csm_contour_map_ce to plot wind speed > but how do I overlay wind direction on it using gsn_vector plot, as it > needs both u and v in the resource. Is there any example available on how > to plot wind speed and direction together ? > > Thanks > Debasish > -------------- next part -------------- An HTML attachment was scrubbed... URL: From debasish.hazra5 at gmail.com Fri Sep 22 21:09:29 2023 From: debasish.hazra5 at gmail.com (Debasish Hazra) Date: Fri, 22 Sep 2023 23:09:29 -0400 Subject: [ncl-talk] Wind vector question Message-ID: Hi, Is there a way to plot wind vector wind RMSE instead of U and V separately using NCL. I have u and v wind from model and analysis. Thanks Debasish -------------- next part -------------- An HTML attachment was scrubbed... URL: From hartten at colorado.edu Sun Sep 24 17:57:23 2023 From: hartten at colorado.edu (Leslie Hartten (CU)) Date: Sun, 24 Sep 2023 17:57:23 -0600 Subject: [ncl-talk] Wind vector question In-Reply-To: References: Message-ID: Hi Debasish, ? If you want to do statistics with vector wind properly, you will need to be using special functions.? This sub-specialty is called "circular statistics" or "directional statistics".? I have found N. I. Fisher's book (_Statistical Analysis of Circular Data_, Cambridge University Press, 1993) to be the most readable of the few that are out there.? It comes with lots of examples drawn from geology, meteorology, and animal movement studies, which helps make sense of the new term names and uses.? There are some errata collected over the last 30 years, and they can be found at https://valuemetrics.com.au/resources/#other? There is pretty solid MATLAB code available for circular statistics (see https://www.mathworks.com/matlabcentral/fileexchange/10676-circular-statistics-toolbox-directional-statistics), and there may also be some for other languages. ? I don't have access to my copy of the book right now, but as I recall RMSE is not actually an appropriate concept with directional data.? However, Fisher's book can show you what would be an appropriate substitute. ? Note that I've got no "ties" to Fisher's work other than I've found it clear and useable. Cheers, ? Leslie -- Dr. Leslie M. Hartten, retired formerly of Univ. of Colorado's ? Cooperative Institute for Research in Environmental Sciences (CIRES) at the NOAA Physical Sciences Laboratory -- Disclaimer:? The contents of this message are mine personally and do not necessarily reflect any position of the University of Colorado. On 9/22/23 9:09 PM, Debasish Hazra via ncl-talk wrote: > Hi, > Is there a way to plot wind vector wind RMSE instead of ?U and V > separately using NCL. I have u and v wind from model and analysis. > > Thanks > Debasish > > _______________________________________________ > ncl-talk mailing list > ncl-talk at mailman.ucar.edu > List instructions, subscriber options, unsubscribe: > https://mailman.ucar.edu/mailman/listinfo/ncl-talk