Questions tagged [julia]
Julia is a high-level, high-performance dynamic programming language for technical computing. It addresses the two-language problem by combining the ease of use of languages such as R and Python with the performance of C and Fortran.
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Auto differentiation with JAX in python and ForwardDiff.jl in Julia give matrices with different values but same structure. Are the results right?
Using ForwardDiff in Julia gives me the following values for 2 matrices
I have tried to use JAX to auto differentiate the same function in Python but I am getting
the following results for A and B ...
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Problems performing 1D-FDTD for dispersive dielectric uisng lorentz model in Julia
So I am trying to model a dispersive dielectric using the Lorentz model in Julia, more specifically I am trying to obtain the frequency-dependent reflectivity of the material. I am ultimately trying ...
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Solving $(I-Q)x={\bf 1}$ for sub-stochastic sparse $Q$ of dimension 5M $\times$ 5M
I have a (right) sub-stochastic CSC sparse matrix $Q$ of dimension 5 million, with 200 million nonzero entries, which is a nonzero percentage of 0.0008%, so it is indeed extremely sparse. It is not ...
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Packages suitable for numerical optimization of functions with discontinuous gradient at the point of minimum
Are there packages for numerical optimization in julia or python, or in any other system for scientific computing, capable of taking into account the discontinuity of gradient at the minimum point? ...
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non zero dirichlet boundary condition entered in weak form
i am trying to write a julia code for linear elasticity in my case i dont have body force and traction but there is a nonzero drichlet bc(ubc) i want to engage the bc in weak form in linear part. is ...
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Optimization of the log-absolute: reformulating to DCP-compliant on Julia
I am trying to reformulate this optimization problem in order to get a DCP-complaint expression on Julia (I am using the ...
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Implementation of integration schemes for ordinary differential equations in Python and peformance comparison
I look for a book/manual where I can find implementations of different integration schemes for ordinary differential equations (like 4-th order Runge-Kutta) in Python with Numba.
To be more specific, ...
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solving a Algebraic Differential Equation in Julia using modelingToolKit.JL
I'm trying to solve a differential algebraic equation in Julia's modelingTookKit.JL, where the vector field has the form f(X) = 0.
I found an example of a DAE in the below link
modelingToolkit.JL DAE](...
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Solving DAE in Julia using GPUs
I'm trying to solve a Differential Algebraic Equation (DAE) in Julia which is very computationally expensive using GPUs. I'm brand new to Julia and don't have much experience coding with GPUs. The ...
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PETSc-like library for Julia
I want to build an application for Material Point Method (and probably other meshfree methods too) in Julia and I am looking for library for direct and iterative solvers that can help me with it. One ...
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Recommendations for ODE solvers for stiff equations
I'm continuing the research of a former Ph.D. student in my group requiring the solution of a system of ODEs. On a technical note, they wrote:
The system of Boltzmann equations behaves numerically ...
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Solving chain of ODE in Julia
I am solving two different ODE whose solutions need to be matched. I am currently doing this by hand, which works great, but I would like to automatise this process. The second ODE takes one of its ...
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ODE Instability with sinh and cosh functions in Julia
I want to solve the first-order differential equation
$$ \begin{align}
\frac{d\alpha}{d\phi} = \frac{\phi \sigma^2 \sin(2d\alpha)+2d\sinh(\sigma^2\alpha \phi)}{-\alpha \sigma^2 \sin(2d\alpha) +2d\...
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Accuracy issues with Arpack in Julia for eigenvalues of smallest magnitude
Following the documentation of Julia's Arpack package (Cf. https://julialinearalgebra.github.io/Arpack.jl/stable/eigs/) I have computed some largest and smallest magnitude eigenvalues of sparse ...
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Is LAPACK behind the cutting edge of dense linear algebra?
I have been digging into some numerical linear algebra lately, and reading in particular about how LAPACK solves symmetric eigenvalue problems. I noticed that the ...
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