2024-03-12 10:56:14 +0200 | answered a question | the plot of my function EFF is always zero, but print Use plot(lambda x: EEF(x, 2), x, 0, 3) See the detailed explanations from cell 28 in this tutorial notebook: https:/ |
2024-03-11 11:30:40 +0200 | commented question | Can't install SageMath 10.2 with conda Maybe the discussion in this thread is relevant: https://groups.google.com/g/sage-devel/c/GaQHdu0Q6UU |
2024-02-29 07:53:30 +0200 | received badge | ● Nice Answer (source) |
2024-02-28 11:49:56 +0200 | answered a question | Combine sage plot with matplotlib What about something like c_matplotlib = c.matplotlib(figure=fig, sub=ax) |
2024-02-28 11:20:08 +0200 | edited answer | Confused about covariant derivatives and tensors in SageMath SageMath's covariant derivatives are documented at https://doc.sagemath.org/html/en/reference/manifolds/sage/manifolds/d |
2024-02-28 11:02:20 +0200 | answered a question | Confused about covariant derivatives and tensors in SageMath SageMath's covariant derivatives are documented here: https://doc.sagemath.org/html/en/reference/manifolds/sage/manifold |
2024-02-19 21:49:48 +0200 | commented question | Comparison between SageMath ODE solvers and Scipy ODE solvers Note that the geodesic solver already implemented in SageMath allows one to choose between many ODE solvers, from SciP |
2024-02-19 21:49:14 +0200 | commented question | Comparison between SageMath ODE solvers and Scipy ODE solvers Note that the geodesic solver already in SageMath allows one to choose between many ODE solvers, from SciPy or from the |
2024-02-19 21:48:39 +0200 | commented question | Comparison between SageMath ODE solvers and Scipy ODE solvers Note that the geodesic solver already implemented in SageMath allows one to choose between many ODE solvers, from SciPy |
2024-02-19 21:48:23 +0200 | commented question | Comparison between SageMath ODE solvers and Scipy ODE solvers Note that the geodesic solver already implemented in SageMath allows one to choose between many ODE solvers, from SciPy |
2024-02-19 21:46:45 +0200 | commented question | Comparison between SageMath ODE solvers and Scipy ODE solvers Note that the geodesic solver already implemented in SageMath allows one to choose between many ODE solvers, from SciPy |
2024-02-17 21:20:51 +0200 | answered a question | Is it possible to use a Bitmap Image as a Graphics object? FWIW, it is possible to superpose a SageMath plot to a png image, via Matplotlib. The first step is to convert the plot |
2024-01-18 07:55:20 +0200 | received badge | ● Nice Answer (source) |
2024-01-13 14:38:44 +0200 | answered a question | Computing the Chern–Pontryagin invariant You have to access to the tensor components by directly passing the indices to the operator [], not via a string (as @to |
2024-01-03 15:16:09 +0200 | commented answer | Connection Forms not Anti-Symmetric Indeed, if the frame argument is not provided, the connection 1-forms are computed for the manifold's default frame, see |
2024-01-03 15:15:39 +0200 | commented answer | Connection Forms not Anti-Symmetric Indeed, if the frame argument is not provided, the connection 1-forms are computed for the manifold's default frame, see |
2023-12-24 14:56:28 +0200 | edited answer | How can I connect Jupyter with SageMath kernel? You must have the Ubuntu package sagemath-jupyter installed on your system. Then you should launch Jupyter from the Sage |
2023-12-24 14:28:15 +0200 | answered a question | How can I connect Jupyter with SageMath kernel? You must have the Ubuntu package sagemath-jupyter installed on your system. Then you should launch Jupyter from the Sage |
2023-12-24 14:06:40 +0200 | answered a question | Command matrix() not work, but worked before It works for me with SageMath 10.2. Are you sure you are running a SageMath kernel and not a Python kernel? If yes, plea |
2023-12-09 11:08:43 +0200 | answered a question | Plotting transition-of-transition fails with "cannot evaluate symbolic expression" Hi, The composition transit_H_to_X = transit_Y_to_X * transit_H_to_Y works well for me (Sage 10.2): it yields a result |
2023-12-05 09:43:43 +0200 | commented question | How to collect the derivatives in an expression for a scalar field It should be diff(f)[i].expr() for $\partial f /\partial x^i$, so I guess commutator_f.expr().collect(diff(f)[0].expr() |
2023-12-02 12:08:38 +0200 | answered a question | cannot use .str() on kernel of Matrix ? You can use str(k) to get a string representation of k. |
2023-11-29 08:59:04 +0200 | commented answer | I want to calculate the Riemann tensor and Kretschmann scalar for Kerr- De Sitter spacetime but it is taking too long and not giving any answer please help Actually, since $\Xi := 1 + H_0^2 a^2$ is a constant, one can rescale the $t$ of https://arxiv.org/abs/1805.00243 as $t' |
2023-11-29 08:57:23 +0200 | commented answer | I want to calculate the Riemann tensor and Kretschmann scalar for Kerr- De Sitter spacetime but it is taking too long and not giving any answer please help Actually, since $\Xi := 1 + H_0^2 a^2$ is a constant, one can rescale the $t$ of https://arxiv.org/abs/1805.00243 as $t' |
2023-11-29 08:57:13 +0200 | commented answer | I want to calculate the Riemann tensor and Kretschmann scalar for Kerr- De Sitter spacetime but it is taking too long and not giving any answer please help Actually, since $\Xi := 1 + H_0^2 a^2$ is a constant, one can rescale the $t$ of https://arxiv.org/abs/1805.00243 as $t' |
2023-11-29 08:56:50 +0200 | commented answer | I want to calculate the Riemann tensor and Kretschmann scalar for Kerr- De Sitter spacetime but it is taking too long and not giving any answer please help Actually, since $\Xi := 1 + H_0^2 a^2$ is a constant, one can rescale the $t$ of https://arxiv.org/abs/1805.00243 as $t' |
2023-11-29 08:55:51 +0200 | commented answer | I want to calculate the Riemann tensor and Kretschmann scalar for Kerr- De Sitter spacetime but it is taking too long and not giving any answer please help Actually, since $\Xi := 1 + H_0^2 a^2$ is a constant, one can rescale the $t$ of https://arxiv.org/abs/1805.00243 as $t' |
2023-11-29 08:54:49 +0200 | commented answer | I want to calculate the Riemann tensor and Kretschmann scalar for Kerr- De Sitter spacetime but it is taking too long and not giving any answer please help Actually, since $\Xi := 1 + H_0^2 a^2$ is a constant, one can rescale the $t$ of https://arxiv.org/abs/1805.00243 as $t' |
2023-11-29 08:54:27 +0200 | commented answer | I want to calculate the Riemann tensor and Kretschmann scalar for Kerr- De Sitter spacetime but it is taking too long and not giving any answer please help Actually, since $\Xi := 1 + H_0^2 a^2$ is a constant, one can rescale the $t$ of https://arxiv.org/abs/1805.00243 as $t' |
2023-11-29 08:46:12 +0200 | commented answer | I want to calculate the Riemann tensor and Kretschmann scalar for Kerr- De Sitter spacetime but it is taking too long and not giving any answer please help I think that the metric given by Eq. (1) of your reference (https://arxiv.org/abs/1710.00997) is not correct (compare wi |
2023-11-28 20:07:57 +0200 | commented answer | I want to calculate the Riemann tensor and Kretschmann scalar for Kerr- De Sitter spacetime but it is taking too long and not giving any answer please help I think that the metric given by Eq. (1) of your reference (https://arxiv.org/abs/1710.00997) is not correct (compare wi |
2023-11-28 15:26:45 +0200 | edited answer | I want to calculate the Riemann tensor and Kretschmann scalar for Kerr- De Sitter spacetime but it is taking too long and not giving any answer please help The 5-dimensional Kerr-AdS spacetime has been treated there. The Riemann tensor was computed in a reasonable time (it i |
2023-11-28 15:02:06 +0200 | edited answer | I want to calculate the Riemann tensor and Kretschmann scalar for Kerr- De Sitter spacetime but it is taking too long and not giving any answer please help The 5-dimensional Kerr-AdS spacetime has been treated there. The Riemann tensor was computed in a reasonable time (it i |
2023-11-28 13:20:54 +0200 | commented answer | I want to calculate the Riemann tensor and Kretschmann scalar for Kerr- De Sitter spacetime but it is taking too long and not giving any answer please help Sorry I read your post too fast. I have updated my answer to the Kerr-de Sitter case. |
2023-11-28 12:15:58 +0200 | commented answer | I want to calculate the Riemann tensor and Kretschmann scalar for Kerr- De Sitter spacetime but it is taking too long and not giving any answer please help I have updated my answer to the Kerr-de Sitter case. |
2023-11-28 12:14:56 +0200 | edited answer | I want to calculate the Riemann tensor and Kretschmann scalar for Kerr- De Sitter spacetime but it is taking too long and not giving any answer please help The 5-dimensional Kerr-AdS spacetime has been treated there. The Riemann tensor was computed in a reasonable time (it i |
2023-11-28 10:22:33 +0200 | commented question | I want to calculate the Riemann tensor and Kretschmann scalar for Kerr- De Sitter spacetime but it is taking too long and not giving any answer please help [2]: M = Manifold(4, 'M', latex_name=r'\mathcal{M}', structure='Lorentzian') [3]: BL.<t,r,th,ph> = M.chart(r"t r t |
2023-11-27 16:56:18 +0200 | answered a question | I want to calculate the Riemann tensor and Kretschmann scalar for Kerr- De Sitter spacetime but it is taking too long and not giving any answer please help The 5-dimensional Kerr-AdS spacetime has been treated there. The Riemann tensor was computed in a reasonable time (it i |
2023-11-26 18:48:18 +0200 | commented answer | How to define a vector field over a chart? It works for me with SageMath 10.1. Which version of SageMath are you using? What is your operating system? |
2023-11-26 16:29:26 +0200 | edited answer | How to define a vector field over a chart? You can define a vector field by providing its components in the default frame like this: v = E.vector_field((function( |
2023-11-26 16:02:14 +0200 | answered a question | How to define a vector field over a chart? You can define a vector field by providing its components in the default frame like this: v = E.vector_field((function( |
2023-11-26 15:46:27 +0200 | edited question | How to define a vector field over a chart? How to define a vector field over a chart? Hello, I have the following code in sage: E.<x,y,z> = EuclideanSpace() |
2023-11-26 15:45:56 +0200 | commented answer | Wrong result for gradient in spherical coordinates I have edited my answer to show how to a new vector frame and express the gradient in it. |
2023-11-26 15:44:38 +0200 | edited answer | Wrong result for gradient in spherical coordinates The answer provided by Sage for the gradient of f is correct: grad(f) = d(F)/dr ∂/∂r + d(F)/dθ/r^2 ∂/∂θ + d(F)/dϕ/(r^2* |
2023-11-25 18:00:50 +0200 | edited answer | Wrong result for gradient in spherical coordinates The answer provided by Sage for the gradient of f is correct: grad(f) = d(F)/dr ∂/∂r + d(F)/dθ/r^2 ∂/∂θ + d(F)/dϕ/(r^2* |
2023-11-25 17:59:34 +0200 | answered a question | Wrong result for gradient in spherical coordinates The answer provided by Sage for the gradient of f is correct: grad(f) = d(F)/dr ∂/∂r + d(F)/dθ/r^2 ∂/∂θ + d(F)/dϕ/(r^2* |
2023-11-23 14:07:28 +0200 | commented answer | grad on a generic metric Actually, parallelism is broken for computations involving symbolic functions (i.e. defined via function as in your case |
2023-11-21 14:51:30 +0200 | answered a question | grad on a generic metric Your code works for me with SageMath 10.1 (the latest stable version). Which version of SageMath are you using? |
2023-11-21 11:22:35 +0200 | answered a question | [CoCalc][SageManifolds] Error : Black hole rendering with SageMath 3 The notebook Black hole rendering with SageMath works well on my CoCalc account with the SageMath 10.0 kernel (not the 1 |
2023-11-20 19:20:08 +0200 | commented question | show(x^2+5) is Showing blank jupyter shell. It works for me with SageMath 10.1. Which version of SageMath are you using? What is your operating system? |