A powerful mathematical programming software with high level symbolic manipulation capacity.
0
votes
0answers
38 views
over fitting avoidance
I distributed my data into 90% training and 10% testing, then I build a boosting regression model using GBM boosting package in R which is very similar to the famous Adaboost regression model. There ...
3
votes
1answer
369 views
Laplace's equation problem in Polar Coordinates (Edit)
Is there public code in Matlab for solving the Laplace equation in polar coordinates in a circular domain?
I tried a lot but my level of matlab and mathematica is not good enough, but still not ...
5
votes
2answers
229 views
Numerical Green functions for a nonlinear wave equation
I am trying to put down some code to get numerically the solution of the following PDE:
$$
\partial^2_t\phi-\partial^2_x\phi+\lambda\phi^3=\delta(x)\delta(t).
$$
Of course, there are several ...
2
votes
2answers
158 views
Numerical solution of fractional integro-diffrential equ. using collocation method?
problem comes from
"Numerical solution of fractional integro-differential , equations by collocation method , E.A. Rawashdeh, Department of Mathematics, Yarmouk University, Irbid 21110, Jordan"
...
5
votes
3answers
2k views
Solving two coupled non-linear second order differential equations numerically
I have encountered the following system of differential equations in lagrangian mechanics. Can you suggest a numerical method, with relevant links and references on how can I solve it, and the ...
4
votes
2answers
414 views
Implementing a finite difference method in Mathematica
I am trying to iterate the following equation
$$
x_{k}(n+1)=x_k (n)-\epsilon (x_{k+1}(n)-2x_k(n) +x_{k-1}(n))+\sqrt{\epsilon}\; \eta_{k}(n)
$$
where $n$ denotes which time step I'm on and $k$ is the ...
4
votes
1answer
61 views
Migdal Recursion and Mathematica
I am studying $SU(2)$ lattice field theory, and I am attempting to use migdal recursion for renormalization.
The main equation for Migdal recursion for my case is
$$e^{-S_p(U,\lambda a)}=\left[ ...
2
votes
2answers
30 views
The region of allowed values for solving the equation in Mathematica
In[2]:= Solve[sqrt(2x-9) == sqrt(4x+3), x]
Out[2]= {{x -> -6}}
But mathematically there is no solution, since sqrt (-21) is not defined. There is a flag that ...
7
votes
0answers
301 views
Replacing Mathematica's QuasiMonteCarlo integration in C++
I have a Mathematica program which performs some integrals in 3 or 4 dimensions using the QuasiMonteCarlo method. The problem is, it takes an annoyingly long time ...
