On 10/03/2011 03:00 PM, Benjamin Root wrote: > On Mon, Oct 3, 2011 at 6:51 PM, questions anon <questions.a...@gmail.com > <mailto:questions.a...@gmail.com>> wrote: > > Hi All, > Is there a simple way to plot a directional arrow to represent a degree? > I have a netcdf file containing wind direction as degrees and I > would like to make a plot with all little arrows representing the > wind direction. > Below is the code I am using currently to plot wind direction but am > not sure where/how to add directional arrows. > Thanks > > > from netCDF4 import Dataset > import numpy as N > import pylab as plt > from numpy import ma as MA > from mpl_toolkits.basemap import Basemap > import os > > ncfile=Dataset('E:/WINDDIR/IDZ00026_VIC_ADFD_Wind_Dir_SFC.nc', 'r+', > 'NETCDF4') > WDIR=ncfile.variables['Wind_Dir_SFC'][-50] > LAT=ncfile.variables['latitude'][:] > LON=ncfile.variables['longitude'][:] > TIME=ncfile.variables['time'][-50] > fillvalue=ncfile.variables['Wind_Dir_SFC']._FillValue > WDIR=MA.masked_values(WDIR, fillvalue) > ncfile.close() > > map = Basemap(projection='merc',llcrnrlat=-40,urcrnrlat=-33, > llcrnrlon=139.0,urcrnrlon=151.0,lat_ts=0,resolution='i') > x,y=map(*N.meshgrid(LON,LAT)) > map.drawstates() > map.drawcoastlines() > plt.title('Wind Direction') > CS = map.contourf(x,y,WDIR,15, cmap=plt.cm.jet) > l,b,w,h =0.1,0.1,0.8,0.8 > cax = plt.axes([l+w+0.025, b, 0.025, h]) > plt.colorbar(CS,cax=cax,drawedges=True) > plt.savefig((os.path.join('E:/WINDDIR/', 'WDIRSFC.png'))) > plt.show() > > > Would the barb() command do what you want? > > http://matplotlib.sourceforge.net/api/pyplot_api.html#matplotlib.pyplot.barbs > http://matplotlib.sourceforge.net/examples/pylab_examples/barb_demo.html > > They aren't arrows, but they are commonly used in meteorology to plot > windfields. > > Cheers, > Ben Root
There is also quiver, both in matplotlib and in basemap. See the quiver_demo.py and barb_demo.py in the basemap examples directory. Eric > > > > ------------------------------------------------------------------------------ > All the data continuously generated in your IT infrastructure contains a > definitive record of customers, application performance, security > threats, fraudulent activity and more. Splunk takes this data and makes > sense of it. Business sense. IT sense. Common sense. > http://p.sf.net/sfu/splunk-d2dcopy1 > > > > _______________________________________________ > Matplotlib-users mailing list > Matplotlib-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/matplotlib-users ------------------------------------------------------------------------------ All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity and more. Splunk takes this data and makes sense of it. Business sense. IT sense. Common sense. http://p.sf.net/sfu/splunk-d2dcopy1 _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
