Hottest Questions This Month

9 votes

1 answer

1k views

Why is it that SVD routines on nearly square matrices run significantly faster than if the matrix was highly non square?

helloworld922

2,391

modified Nov 10 at 6:32

5 votes

2 answers

438 views

Number of function calls and jacobian calls in scipy.root

Tarik

173

modified Nov 29 at 8:14

3 votes

1 answer

175 views

Stability of Euler forward method

lightxbulb

1,271

modified Nov 13 at 9:19

3 votes

1 answer

241 views

Finite difference problem

Maxim Umansky

2,440

modified 12 hours ago

2 votes

1 answer

156 views

Solving non-linear partial differential equation numerically: $u_{xx}+u_{yy}=\mathrm{e}^{u}$

Evgeny

21

modified Nov 27 at 19:03

3 votes

1 answer

185 views

Solving underdetermined Lyapunov equation?

Federico Poloni

11.1k

modified Nov 19 at 8:28

1 vote

2 answers

96 views

Implementing matrix term version of Gauss-seidel

Carllos Limma

111

modified Nov 28 at 11:33

0 votes

1 answer

74 views

Are there any established direct eigensolvers for sparse hermitian matrices?

Wolfgang Bangerth

54.2k

answered Dec 2 at 3:45

2 votes

1 answer

143 views

Where am I making a mistake in solving the heat equation using the spectral method (Chebyshev's differentiation matrix)?

ConvexHull

1,253

modified 2 days ago

2 votes

1 answer

82 views

enough conditions to check that a matrix doesn't have Cholesky factorization while factorizing it

Abdullah Ali Sivas

2,411

answered Nov 13 at 20:33

2 votes

1 answer

142 views

In linear programming, is there a way to constrain two variables to not have opposite sign

Thijs Steel

1,406

answered 3 hours ago

1 vote

1 answer

139 views

Solving PDEs using FEM using cubic Hermite polynomials

IPribec

544

modified Nov 30 at 11:21

2 votes

1 answer

128 views

Large set of nonlinear equations in Sympy

mmikkelsen

369

answered Nov 29 at 13:50

0 votes

1 answer

96 views

Step size constraint in Euler backward

Lutz Lehmann

5,544

modified Dec 2 at 12:45

1 vote

1 answer

116 views

Calculating Hypergeometric1F1 for large arguments

nicoguaro♦

8,370

answered Nov 14 at 14:56

2 votes

1 answer

113 views

How to formulate a convex expression to minimize the difference between Frobenius norm of a positive semidefinite matrix and a positive value

tyrela

21

modified Nov 23 at 1:59

1 vote

1 answer

86 views

Symmetry axis boundary condition

Nikola Ristic

227

answered Nov 25 at 22:15

2 votes

3 answers

202 views

Approximation of derivatives in the finite volume method

Matthew Hunt

131

answered Nov 23 at 12:03

1 vote

1 answer

71 views

accuracy problem for a null space calculation on a sparse rectangular matrix

Federico Poloni

11.1k

answered yesterday

2 votes

1 answer

89 views

references for optimization in the context of parameter identification with finite elements

whpowell96

2,054

modified Nov 25 at 17:53

5 votes

0 answers

114 views

Single precision vs double precision conjugate gradients

lightxbulb

1,271

asked Nov 17 at 14:08

2 votes

1 answer

82 views

Need help with the python code: Calculating Madelung constant CsCl crystal structure

Anton Menshov♦

8,602

modified Nov 10 at 19:57

2 votes

1 answer

76 views

Solving for $X$ in $\sum_{a,b} b a^T b^T X a = Y$

Federico Poloni

11.1k

answered Dec 1 at 15:36

4 votes

0 answers

120 views

FVM for non-regular domain with triangular mesh

VIVID

91

modified Nov 19 at 11:17

3 votes

0 answers

112 views

Stochastic power iteration for generalized eigenvalue problems?

Yaroslav Bulatov

2,273

modified Nov 10 at 16:01

1 vote

1 answer

83 views

Adding a diffusion term to the MUSCL - Kurganov and Tadmor central scheme

ConvexHull

1,253

answered Nov 15 at 7:35

1 vote

1 answer

82 views

derivative matrix and the Dirac delta distribution

Wolfgang Bangerth

54.2k

answered Nov 10 at 15:15

1 vote

1 answer

72 views

Does anyone know how to add a forcing term at the center of a cicular membrane?

Konstantinos

25

modified Nov 22 at 2:44

0 votes

1 answer

67 views

How to plot the power spectrum

138 Aspen

133

modified Nov 25 at 2:09

0 votes

0 answers

81 views

A confusion about the bubble function in lumped mass FEM

Maxim Umansky

2,440

modified Nov 16 at 20:30

1 vote

1 answer

63 views

Numerically computing envelope of Gibbs oscillation

Yimin

111

answered 2 days ago

-1 votes

1 answer

38 views

Gmsh problems in Google Colab, visualize mesh

Zoltán Csáti

747

answered yesterday

0 votes

1 answer

44 views

draw a log-log plot of MSD (mean square displacement) versus `t` of a movement of the polymer chain

Wolfgang Bangerth

54.2k

answered Nov 19 at 0:08

3 votes

0 answers

70 views

How is the Alternating Schwarz Method used as a Preconditioner to a Krylov Method?

Jared Frazier

233

modified Nov 24 at 17:32

0 votes

1 answer

53 views

Local truncation error of given implicit 1-step scheme

Lutz Lehmann

5,544

answered Nov 12 at 19:13

3 votes

0 answers

64 views

Efficient Algorithm for LU-Factorization of Modified Matrix with Last Column Alteration If We Have Its Not-Modified LU-Factorization

Ilkay Burak

155

asked Nov 9 at 15:29

0 votes

0 answers

59 views

Softening vs Smoothing Length... Is There a Difference?

dcro

1

modified Nov 19 at 17:37

1 vote

1 answer

45 views

Finding the Vector $v$ for a Given Householder Matrix Transformation of Non-Collinear Vectors $a$ and $b$

Lutz Lehmann

5,544

modified Dec 2 at 6:27

2 votes

0 answers

57 views

Numerical integration in Fourier space over 3D grid

JasonC

31

modified Nov 16 at 3:05

0 votes

0 answers

55 views

How to set Neumann BC for coupled transport problem in weak form?

l'étudiant

1

modified Nov 7 at 17:58

0 votes

0 answers

49 views

eigenvalues of inhomogeneous Helmholtz equation violate superposition using FEM

Ekrem Ekici

11

asked Nov 29 at 21:21

1 vote

0 answers

49 views

Overlap matrix and its inverse matrix

Young Q

11

asked Dec 4 at 1:17

0 votes

0 answers

49 views

ENO-Runge-Kutta discretization

solanin

1

modified 2 days ago

0 votes

0 answers

46 views

Is a sort of "z-drift" the result of numerical precision errors in FDM?

JS4137

133

asked Nov 15 at 5:24

0 votes

0 answers

43 views

3D Quadrature schemes with points on boundary

whpowell96

2,054

modified Dec 3 at 18:47

2 votes

0 answers

42 views

How to use a preconditioner estimated from a subset of data?

Yaroslav Bulatov

2,273

modified Nov 20 at 19:27

1 vote

0 answers

42 views

Solution to the Liouville-Gibbs equation

homocomputeris

395

asked Nov 14 at 20:27

0 votes

0 answers

37 views

Which numerical method can I use to solve this system of hyperbolic PDEs?

Nikola Ristic

227

modified Dec 1 at 22:35

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