Giovanni's profile - activity

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2011-12-16 03:16:55 +0200	asked a question	"Evaluate All" keyboard shortcut Is there any keyboard shortcut for the notebook command "Evaluate All"? Or in alternative could it be assigned somehow? Thanks a lot!
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2011-11-09 05:40:36 +0200	answered a question	Plotting spherical data I don't think that you can interactively rotate with mplot3d. I'm not an expert anyway. I would say that mayavi2 experimental package fits your bill anyway. I use mayavi2 (outside of Sage) to produce antenna patterns of high quality and works beautifully. I guess you should proceed as follows: 1) Install mayavi2 package following the instruction at this page http://www.sagemath.org/doc/numerical... 2) You invoke mayavi2 with something like this (http://www.sagemath.org/doc/numerical...) `import numpy from mayavi.tools import imv x=numpy.arange(-8,8,.2) def f(x,y): r=numpy.sqrt(x2+y2)+.01 return numpy.sin(r)/r imv.surf(x,x,f)` 3) The command you want is mesh(). Read the documentation and the examples here and here hope it helps. Giovanni
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2011-11-08 11:14:46 +0200	marked best answer	2D interpolating function from numpy arrays to spherical-plot3d It's because your f function above is returning a numpy array, rather than a number. `sage: f(1,2) array([[ 0.45712591]]) sage: f(1,2)[0,0] 0.45712590955624677` So you need to extract that number out. You did it in your last example above. Here's another way: `spherical_plot3d(lambda x,y: f(x,y)[0,0],(x,0,2pi),(y,0,pi))` Here is yet another way, since numpy arrays with a single value like that can be cast to floats. `spherical_plot3d(lambda x,y: float(f(x,y)),(x,0,2pi),(y,0,pi))`
2011-11-08 11:13:42 +0200	answered a question	Plotting spherical data I do not think that you can get all of that directly with sage. A viable option would be to call mplot3d (plot_surface) from matplotlib, which is easily done in Sage. This way you can get point 1,2,4 even if the axis are displayed in a different way, and I think also point 3, but i am not sure about that. All the references are here. If you need some kind of interpolation, I suggest you employ scipy.interpolate module. You can get many different types of N dimensional interpolation.
2011-11-04 09:54:11 +0200	commented answer	sage notebook server + ssh tunneling + port forwarding It worked! Thanks a lot!!! This way I can work on my University Cluster!
2011-11-04 09:53:32 +0200	marked best answer	sage notebook server + ssh tunneling + port forwarding Connect via ssh to your server and bind port, e.g. `ssh -L 8000:localhost:8000 user@your.server.com` You can use some extra ssh-options if you want... Run `./sage -notebook` on your server. Open a browser (locally) and type in `http://localhost:8000` BTW: You do not need a X session to your server for that.
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2011-11-03 18:01:41 +0200	asked a question	sage notebook server + ssh tunneling + port forwarding I have access to a remote server through a gate computer with this command: ssh -fN -l user -L port:host:22 gate #To Bring up the tunnel ssh -X -p port user@localhost #To open an X session to my server Once on the server I run sage by typing "./sage" in the installation directory. Now the questions: 1)Which are the right commands to bring up the remote notebook server? 2)What should I type in my local browser? (I suppose something like 'localhost:port', but even without launching the notebook server I get the following error:'SSH-2.0-OpenSSH_4.3 Protocol mismatch') I tried to read the instructions and the wiki, but I confess that I am at a loss. Thanks a lot Giovanni
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2011-11-01 04:57:19 +0200	commented answer	2D interpolating function from numpy arrays to spherical-plot3d Thanks for the answer, the lambda form is especially useful. Nevertheless the fact that plot3d works and spherical_plot3d doesn't is odd
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2011-10-31 07:37:11 +0200	asked a question	2D interpolating function from numpy arrays to spherical-plot3d I need to plot an antenna emission pattern. I am importing data from a tabbed .txt file (theta[i,j],phi[i,j],r[i,j]) as numpy arrays. I then employ the same data to build a 2D interpolating function with the scipy module scipy.interpolate.interp2d. The interpolating function successfully works in plot3d, but somehow breaks spherical_plot3d. Is there anyway to build a working 2D interpolating function for spherical_plot3D? -----Toy Data--------- `v_phi=array([ 0. , 1.57079637, 3.14159274, 4.71238911, 6.28318548]) v_theta=array([ 0. , 0.78539819, 1.57079637, 2.35619456, 3.14159274]) m_r=array([[ 0.16763356, 0.25683223, 0.16649297, 0.10594339, 0.55282422], [ 0.16763356, 0.19993708, 0.31403568, 0.47359696, 0.55282422], [ 0.16763356, 0.25683223, 0.16649297, 0.10594339, 0.55282422], [ 0.16763356, 0.19993708, 0.31403568, 0.47359696, 0.55282422], [ 0.16763356, 0.25683223, 0.16649297, 0.10594339, 0.55282422]])` ------Traceback from spherical_plot3d--------- Traceback (most recent call last): File "<stdin>", line 1, in <module> File "_sage_input_326.py", line 10, in <module> exec compile(u'open("___code___.py","w").write("# -- coding: utf-8 --\\n" + _support_.preparse_worksheet_cell(base64.b64decode("c3BoZXJpY2FsX3Bsb3QzZChmLCh4LDAsMipwaSksKHksMCxwaSksY21hcD0ncGluaycsYWRhcHRpdmU9VHJ1ZSkuc2hvdyhhc3BlY3RfcmF0aW89KDEsMSwxKSk="),globals())+"\\n"); execfile(os.path.abspath("___code___.py")) File "", line 1, in <module> File "/tmp/tmpR1mM9J/___code___.py", line 3, in <module> exec compile(u"spherical_plot3d(f,(x,_sage_const_0 ,_sage_const_2 *pi), (y,_sage_const_0 ,pi),cmap='pink',adaptive=True).show(aspect_ratio=(_sage_const_1 ,_sage_const_1 ,_sage_const_1 ))" + '\n', '', 'single') File "", line 1, in <module> File "base.pyx", line 1052, in sage.plot.plot3d.base.Graphics3d.show (sage/plot/plot3d/base.c:9313) File "base.pyx", line 957, in sage.plot.plot3d.base.Graphics3d._process_viewing_options (sage/plot/plot3d/base.c:9112) File "base.pyx", line 198, in sage.plot.plot3d.base.Graphics3d._determine_frame_aspect_ratio (sage/plot/plot3d/base.c:3404) File "base.pyx", line 214, in sage.plot.plot3d.base.Graphics3d._safe_bounding_box (sage/plot/plot3d/base.c:3521) File "parametric_surface.pyx", line 318, in sage.plot.plot3d.parametric_surface.ParametricSurface.bounding_box (sage/plot/plot3d/parametric_surface.c:2991) File "parametric_surface.pyx", line 366, in sage.plot.plot3d.parametric_surface.ParametricSurface.triangulate (sage/plot/plot3d/parametric_surface.c:3521) File "parametric_surface.pyx", line 361, in sage.plot.plot3d.parametric_surface.ParametricSurface.triangulate (sage/plot/plot3d/parametric_surface.c:3451) File "parametric_surface.pyx", line 576, in sage.plot.plot3d.parametric_surface.ParametricSurface.eval_grid (sage/plot/plot3d/parametric_surface.c:5152) File "<string>", line 4, in <lambda> File "expression.pyx", line 3501, in sage.symbolic.expression.Expression.substitute (sage/symbolic/expression.cpp:15529) File "expression.pyx", line 2089, in sage.symbolic.expression.Expression.coerce_in (sage/symbolic/expression.cpp:10788) File "parent_old.pyx", line 229, in sage.structure.parent_old.Parent._coerce_ (sage/structure/parent_old.c:3420) File "parent.pyx", line 1047, in sage.structure.parent.Parent.coerce (sage/structure/parent.c:7734) TypeError: no canonical coercion from <type 'numpy.ndarray'> to Symbolic Ring ------------Code------------- `#importing Libraries import numpy as np import scipy import scipy.interpolate #Importing data data=np.loadtxt('/home/giova/data/work/electrodynamics/gmm/shell/maps/test.msc') #getting the data theta=data[:,0] phi=data[:,1] r=data[:,2]; #reshaping the ...` (more)