Contour Plot in Sage and Matplotlib

Today I was playing around with Matplotlib and Sage(math) for plotting the relativistic addition of velocities. First I tried the classic 3-dimensional plot in Sage, var(‘x,y’) p = plot3d((x+y)/(1+x*y), (x,0,.99), (y,0,.99), color=hue(0.8)) p.save(‘Vel-3d.png’) However the plot was not so enlighten. So I tried a contour plot, var(‘x’) p = contour_plot((x+y)/(1+x*y), (x,0,.99), (y,0,.99), contours=[0.3,0.2,.5,.7,.9,.99], cmap=’hsv’, labels=True, [...]

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Enable Java Plugin on Firefox 3.6 (Karmic)

Pre-requisites. I don’t know how much of it its really needed, but I install the whole Sun’s Java 6 packages, $ sudo apt-get install sun-java6-jdk sun-java-6-jre sun-java6-pluging sun-java6-source sun-java6-bin For sure you’ll need the jdk and plugin one… If your internet connection is slow you might try installing these two first and try the above [...]

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Playing around with Sage(math)

I was playing with Sage(math) because I wanted to manage (a bit) the presentation of the plots. Here is what I found out! (most of it is in Sage help) Color of Plots. For changing the color of the plot, use the option color, sage: plot(sin, -3, 3, color=’red’) and you’ll get Nice! but not [...]

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Sage and Mathematica integration

Last week I was trying to integrate a power of the Hyperbolic Tangent  (tanh) in sage, so I first try, sage: n,x = var(‘n,x’) sage: integrate(tanh(x)^n, x) but Sage didn’t integrate it. So I impose to be an integer, sage: n,x = var(‘n,x’) sage: assume(n, ‘integer’) sage: integrate(tanh(x)^n, x) and still nothing. However, for specific [...]

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Weak Points in Sage(math)

I’ve been trying Sage(math) for the last three weeks, and I can say it’s a charming piece of software. Works very well, the IRC channel is really, really helpful, the interface is simple, the Python platform is rather natural to manage, evolves quickly… and so on. However, there are some weak points I’d like to [...]

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