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Kernel: SageMath 9.2
version()

NEW: 3D Animations!

x, y = var('x, y') def build_frame(t): """Build a single frame of animation at time t.""" e = parametric_plot3d([sin(2*x - t), sin(x + t), x], (x, 0, 2*pi), color='red') b = parametric_plot3d([cos(x + t), -sin(x - t), x], (x, 0, 2*pi), color='green') return e + b frames = [build_frame(t) for t in (0, pi/32, pi/16, .., 2*pi)] animate(frames, delay=5).interactive(projection='orthographic')

eigenvalues with errors using Arb

from sage.matrix.benchmark import hilbert_matrix mat = hilbert_matrix(5).change_ring(CBF) mat.eigenvalues()

Polyomino tilings

from sage.combinat.tiling import Polyomino H = Polyomino([ (-1, 1), (-1, 4), (-1, 7), (0, 0), (0, 1), (0, 2), (0, 3), (0, 4), (0, 5), (0, 6), (0, 7), (0, 8), (1, 1), (1, 2), (1, 3), (1, 4), (1, 5), (1, 6), (1, 7), (1, 8), (2, 0), (2, 2), (2, 3), (2, 5), (2, 6), (2, 8)]) H.show2d()
%time solution = H.self_surrounding(10, ncpus=2)
G = sum([p.show2d() for p in solution], Graphics()) G

Manifolds: diff function for exterior derivatives

M = Manifold(2, 'M') X.<x,y> = M.chart() f = M.scalar_field(x^2*y, name='f') diff(f)
diff(f).display()
a = M.one_form(-2*x*y, x, name='a'); a.display() diff(a).display()

Differential Weyl algebra

W.<x,y> = DifferentialWeylAlgebra(QQ) dx, dy = W.differentials() dx.diff(x^3)
(x*dx + dy + 1).diff(x^4*y^4 + 1)

Temperley-Lieb diagrams now have unicode

from sage.combinat.diagram_algebras import TL_diagram_ascii_art TL = [(-15,-12), (-14,-13), (-11,15), (-10,14), (-9,-6), (-8,-7), (-5,-4), (-3,1), (-2,-1), (2,3), (4,5), (6,11), (7, 8), (9,10), (12,13)] TL_diagram_ascii_art(TL, use_unicode=True)

some calculus

x = var('x') eq = 6*x^6 - 7*x^5 - 7*x^4 + 7*x^2 + 7*x - 6 sol = solve(eq, x) sol
show(sol)
plot(eq, (x, -1.1, 1.6))
eq = 6*x^6 - 7*x^5 - 7*x^4 + 7*x^2 + 7*x - 6 complex_plot(eq, (-1.5, 2.1), (-1.5, 1.5))
sage: P = polytopes.cube(intervals='zero_one') # obtain others than the standard cube sage: P = matrix([[0,1,0],[0,1,1],[1,0,0]])*P # linear transformations sage: it = P.face_generator() # a (fast and efficient) face generator sage: next(it)

Generator for cube-connected cycles

graphs.CubeConnectedCycle(3).plot()

Manifolds

More functionalities in index notation for tensors

E.<x,y> = EuclideanSpace() v = E.vector_field(-y, x) t = E.tensor_field(0, 2, [[1, x], [-2*y, x^2]]) v['j']*(t['_ij'] + t['_ji']) == v.contract(2*t.symmetrize())
v
t
v['j'], t['_ij'], t['_ji']
t.symmetrize()
@interact def func(k = slider(0, 10, .1), j = (-10, 10), l = range_slider(-5, 5)): print("k: %s" % k) print("j: %s" % j) print("l: [%s, %s]" % l)
var('t y') plot_slope_field(y - t, (t,0,10), (y,0,6), plot_points=25)
G = cellular_automata.GraftalLace([2,0,3,3,6,0,2,7]) G
G.evolve(42) G.plot()
init = 200*[1] init[100] = 0 init[101] = 0 ECA = cellular_automata.Elementary(151, width=200, initial_state=init) ECA
ECA.evolve(200) ECA.plot()

Torus

from sage.plot.plot3d.shapes import Torus inner_radius = .3; outer_radius = 1 show(Torus(outer_radius, inner_radius, color='orange'), aspect_ratio=1, spin=3)