Re: [Matplotlib-users] help plotting vector field in basemap
On 2013/04/08 4:13 AM, epi wrote:
Hi All,
i'm new to basemap, truing to learn how to plot vector from a netcdf file
the variables in my file are :
- time
- Significant_height_of_combined_wind_waves_and_swell_surface
- u-component_of_wind_surface
- v-component_of_wind_surface
this is my code, the pcolormesh is fine
import netCDF4
import datetime as dt
import numpy as np
import numpy.ma as ma
from datetime import date, datetime, timedelta
from mpl_toolkits.basemap import Basemap
url='http://geoport.whoi.edu/thredds/dodsC/fmrc/NCEP/ww3/cfsr/4m/best'
#url = 'http://geoport.whoi.edu/thredds/dodsC/fmrc/NCEP/ww3/cfsr/10m/best'
nc = netCDF4.Dataset(url)
#nc.variables.keys()
time_var = nc.variables[str('time')]
wave_var =
nc.variables['Significant_height_of_combined_wind_waves_and_swell_surface']
date = datetime(1991,11,1,12)
istart = netCDF4.date2index(date,time_var,select='nearest')
lat = nc.variables['lat'][:]
lon = nc.variables['lon'][:]
uin = nc.variables['u-component_of_wind_surface'][istart,:,:]
vin = nc.variables['v-component_of_wind_surface'][istart,:,:]
var = wave_var[istart,:,:]
wave = ma.masked_where(np.isnan(var),var)
m = Basemap(llcrnrlon=-71.5,llcrnrlat=39.5,urcrnrlon=-63.0,urcrnrlat=46.0,\
lat_0=20.,lon_0=-60.,lat_ts=20.)
lons, lats = np.meshgrid(lon,lat)
x, y = m(lons, lats)
m.pcolormesh(lon[:], lat[:], wave, vmin=0, vmax=3);
m.quiver(x, y, uin, vin);
Try something like this:
m.quiver(x[::5,::5], y[::5,::5], uin[::5,::5], vin[::5,::5], scale=200);
You can use the scale and the scale_units kwargs to control the arrow
lengths. Quiver plots don't work visually when there are too many
arrows, so given the scale of your plot, you need to subsample the wind
vectors as illustrated.
Eric
.. but the vector plot in overlay doesn't render what i'm looking for ..
obviously my fault in the code
thank you for your precious help!
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Re: [Matplotlib-users] zig-zag to represent suppressed 0 on axis?
At 4:20pm -0400 Sun, 07 Apr 2013, Francesco Montesano wrote: Il giorno 07/apr/2013 21:03, Kevin Hunter Kesling ha scritto: On the other hand, I'm still such a noob at Matplotlib ... is there a way to have one of the subplots take up more than its default 50% allotment? you can give a look at the last two plots in this example http://matplotlib.org/examples/pylab_examples/demo_tight_layout.html or use plot.axes providing the rectangle that you want That is closer to what I want, but still not there. I was finally able to find something that fit the bill to 95% of what I want: http://matplotlib.1069221.n5.nabble.com/Proposal-for-Broken-Axes-td38050.html The first post by 'klukas' does exactly what I asked for. It's a zig-zag on the Y-axis to show that what is graphed is not continuous, and unlike the various official examples, the zig-zag placement is user-specifiable, as opposed to exactly halfway between the top and bottom. The only thing I have yet to figure out how to do is to simultaneously have a zig-zag on the X axis as well -- an artifact of how these zig-zags must be created via multiple axes on the same figure, rather than as built in to the axis artist. For googleability: The above linked graph code enables for matplotlib: - suppressed zeros on the Y-axis of an XY plot - showing suppressed data on the Y-axis - lightning bolt symbol on the Y-axis - zig-zag on the Y-axis - a broken Y-axis Thanks for your pointers, Francesco, as they helped me to fine-tune my Google search terms. And thank you, Klukas, whoever you are. Cheers, Kevin -- Minimize network downtime and maximize team effectiveness. Reduce network management and security costs.Learn how to hire the most talented Cisco Certified professionals. Visit the Employer Resources Portal http://www.cisco.com/web/learning/employer_resources/index.html ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] zig-zag to represent suppressed 0 on axis?
Hi Kevin, I don't check the link you provided very carefully. So I guess you already find a solution. otherwise I have done something similar before and have made a bit general function to do the job, which I think might be helpful for you. You can check the following three functions at https://github.com/ChaoYue/pylsce/blob/master/g.py Calc_Newaxes_Fraction Axes_Replace_Split_Axes Axes_Set_Breakaxis a working example is below: fig,axs = plt.subplots(nrows=2) bottom_ax, top_ax = g.Axes_Replace_Split_Axes(fig,axs[0],split_fraction=[0.36,0.04,0.6],direction='v') g.Axes_Set_Breakaxis(bottom_ax, top_ax, 0.01,0.03,'v') left_ax, right_ax = g.Axes_Replace_Split_Axes(fig,axs[1],split_fraction=[0.38,0.02,0.6],direction='h') g.Axes_Set_Breakaxis(left_ax, right_ax, 0.03,0.02,'h') the figure is as attached. cheers, chao On Mon, Apr 8, 2013 at 9:05 PM, Kevin Hunter [via matplotlib] ml-node+s1069221n40857...@n5.nabble.com wrote: At 4:20pm -0400 Sun, 07 Apr 2013, Francesco Montesano wrote: Il giorno 07/apr/2013 21:03, Kevin Hunter Kesling ha scritto: On the other hand, I'm still such a noob at Matplotlib ... is there a way to have one of the subplots take up more than its default 50% allotment? you can give a look at the last two plots in this example http://matplotlib.org/examples/pylab_examples/demo_tight_layout.html or use plot.axes providing the rectangle that you want That is closer to what I want, but still not there. I was finally able to find something that fit the bill to 95% of what I want: http://matplotlib.1069221.n5.nabble.com/Proposal-for-Broken-Axes-td38050.html The first post by 'klukas' does exactly what I asked for. It's a zig-zag on the Y-axis to show that what is graphed is not continuous, and unlike the various official examples, the zig-zag placement is user-specifiable, as opposed to exactly halfway between the top and bottom. The only thing I have yet to figure out how to do is to simultaneously have a zig-zag on the X axis as well -- an artifact of how these zig-zags must be created via multiple axes on the same figure, rather than as built in to the axis artist. For googleability: The above linked graph code enables for matplotlib: - suppressed zeros on the Y-axis of an XY plot - showing suppressed data on the Y-axis - lightning bolt symbol on the Y-axis - zig-zag on the Y-axis - a broken Y-axis Thanks for your pointers, Francesco, as they helped me to fine-tune my Google search terms. And thank you, Klukas, whoever you are. Cheers, Kevin -- Minimize network downtime and maximize team effectiveness. Reduce network management and security costs.Learn how to hire the most talented Cisco Certified professionals. Visit the Employer Resources Portal http://www.cisco.com/web/learning/employer_resources/index.html ___ Matplotlib-users mailing list [hidden email] http://user/SendEmail.jtp?type=nodenode=40857i=0 https://lists.sourceforge.net/lists/listinfo/matplotlib-users -- If you reply to this email, your message will be added to the discussion below: http://matplotlib.1069221.n5.nabble.com/zig-zag-to-represent-suppressed-0-on-axis-tp40849p40857.html To start a new topic under matplotlib - users, email ml-node+s1069221n...@n5.nabble.com To unsubscribe from matplotlib, click herehttp://matplotlib.1069221.n5.nabble.com/template/NamlServlet.jtp?macro=unsubscribe_by_codenode=2code=Y2hhb3l1ZWpveUBnbWFpbC5jb218MnwxMzg1NzAzMzQx . NAMLhttp://matplotlib.1069221.n5.nabble.com/template/NamlServlet.jtp?macro=macro_viewerid=instant_html%21nabble%3Aemail.namlbase=nabble.naml.namespaces.BasicNamespace-nabble.view.web.template.NabbleNamespace-nabble.view.web.template.NodeNamespacebreadcrumbs=notify_subscribers%21nabble%3Aemail.naml-instant_emails%21nabble%3Aemail.naml-send_instant_email%21nabble%3Aemail.naml -- *** Chao YUE Laboratoire des Sciences du Climat et de l'Environnement (LSCE-IPSL) UMR 1572 CEA-CNRS-UVSQ Batiment 712 - Pe 119 91191 GIF Sur YVETTE Cedex Tel: (33) 01 69 08 29 02; Fax:01.69.08.77.16 break_axis.jpg (182K) http://matplotlib.1069221.n5.nabble.com/attachment/40858/0/break_axis.jpg -- View this message in context: http://matplotlib.1069221.n5.nabble.com/zig-zag-to-represent-suppressed-0-on-axis-tp40849p40858.html Sent from the matplotlib - users mailing list archive at Nabble.com.-- Minimize network downtime and maximize team effectiveness. Reduce network management and security costs.Learn how to hire the most talented Cisco Certified professionals. Visit the Employer Resources Portal
Re: [Matplotlib-users] zig-zag to represent suppressed 0 on axis?
Il giorno 08/apr/2013 21:05, Kevin Hunter Kesling kmhun...@ncsu.edu ha scritto: At 4:20pm -0400 Sun, 07 Apr 2013, Francesco Montesano wrote: Il giorno 07/apr/2013 21:03, Kevin Hunter Kesling ha scritto: On the other hand, I'm still such a noob at Matplotlib ... is there a way to have one of the subplots take up more than its default 50% allotment? you can give a look at the last two plots in this example http://matplotlib.org/examples/pylab_examples/demo_tight_layout.html or use plot.axes providing the rectangle that you want That is closer to what I want, but still not there. I was finally able to find something that fit the bill to 95% of what I want: http://matplotlib.1069221.n5.nabble.com/Proposal-for-Broken-Axes-td38050.html The first post by 'klukas' does exactly what I asked for. It's a zig-zag on the Y-axis to show that what is graphed is not continuous, and unlike the various official examples, the zig-zag placement is user-specifiable, as opposed to exactly halfway between the top and bottom. The only thing I have yet to figure out how to do is to simultaneously have a zig-zag on the X axis as well -- an artifact of how these zig-zags must be created via multiple axes on the same figure, rather than as built in to the axis artist. For googleability: The above linked graph code enables for matplotlib: - suppressed zeros on the Y-axis of an XY plot - showing suppressed data on the Y-axis - lightning bolt symbol on the Y-axis - zig-zag on the Y-axis - a broken Y-axis Thanks for your pointers, Francesco, as they helped me to fine-tune my Google search terms. And thank you, Klukas, whoever you are. I'm half that you found the solution for your problem and to have been useful just providing links. This has been one of the easiest answer I have ever given :) And mostly thanks for sharing your findings. cheers and good night, Fra Cheers, Kevin -- Minimize network downtime and maximize team effectiveness. Reduce network management and security costs.Learn how to hire the most talented Cisco Certified professionals. Visit the Employer Resources Portal http://www.cisco.com/web/learning/employer_resources/index.html___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] verts
Hey List, I've got some verts I stole from the internet that draws an upward arrow (or a down arrow), but I need to draw an arrow to the right or to the left. But I don't really understand verts and how they work. arrowup_verts = [[0.,0.], [-1., -1], [0.,0.], [0.,-2.],[0.,0.], [1,-1]] arrowdown_verts = [[0.,0.], [-1., 1], [0.,0.], [0.,2.],[0.,0.], [1, 1]] plot them like... scatter(1,1,s=100, marker=None, verts=arrowup_verts) Can someone make me new verts for the right and left arrow? Then, maybe tomorrow, explain how I was supposed to know what to do. Thanks y'all Steven -- Steven Boada Doctoral Student Dept of Physics and Astronomy Texas AM University bo...@physics.tamu.edu -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] verts
Thanks Zach, That simple little example makes more sense than the manual page did. Perhaps it's just late. I appreciate it. Steven On Mon Apr 8 22:30:43 2013, Zachary Pincus wrote: I've got some verts I stole from the internet that draws an upward arrow (or a down arrow), but I need to draw an arrow to the right or to the left. But I don't really understand verts and how they work. arrowup_verts = [[0.,0.], [-1., -1], [0.,0.], [0.,-2.],[0.,0.], [1,-1]] arrowdown_verts = [[0.,0.], [-1., 1], [0.,0.], [0.,2.],[0.,0.], [1, 1]] plot them like... scatter(1,1,s=100, marker=None, verts=arrowup_verts) Can someone make me new verts for the right and left arrow? Then, maybe tomorrow, explain how I was supposed to know what to do. Draw a line from (0,0) to (-1, -1) on the X-Y plane, and then to (0,0) again, and then continue so forth for all the (x,y) pairs in arrowup_verts. You will notice they form a nice little arrow pointing up. (At some point in this process, you should note that verts is short for vertices. As in vertices of a polygon or poly-line.) It would seem that the origin of the verts coordinate system is translated to the (x,y) data position at which each marker is plotted. This should give you, I presume, sufficient information to figure out your own left and right arrows, no? Or any other shape you should care to plot... Zach Thanks y'all Steven -- Steven Boada Doctoral Student Dept of Physics and Astronomy Texas AM University bo...@physics.tamu.edu -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users -- Steven Boada Doctoral Student Dept of Physics and Astronomy Texas AM University bo...@physics.tamu.edu -- Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
