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1 vote
0 answers
33 views

Sum with constraints in maple or mathematica [closed]

I'm looking for a code in Maple or Mathematica to evaluate and give a list of terms in expressions like $\newcommand{\on}[1]{\operatorname{#1}}$ $$ \sum_{a\ +\ b\ +\ c\ =\ 6}\on{f}\left(a\right)\on{f}\...
wkmath's user avatar
  • 13
1 vote
0 answers
42 views

How to define a linear operator in Maple that commutes with derivatives?

I would like to simplify an expression involving the Hilbert transform in Maple. The Hilbert transform is defined by $$ Hf(x) = \frac{1}{\pi} \ \mathrm{p.v.} \int_{-\infty}^{+\infty} \frac{f(z)}{z-x} \...
Liu's user avatar
  • 11
1 vote
0 answers
83 views

Conditions on the coefficients that the roots of a polynomial be less that or equal to unity in absolute value

Consider the polynomial $$f(x)=p_0x^n+p_1x^{n-1}+...+p_{n-1}x+p_n,~p_i \in \mathbb C.$$ Particularly, in the case of absolute stability of a multi-step numerical method, how can we find out the ...
Riaz's user avatar
  • 2,184
3 votes
1 answer
139 views

How to do a fast numerical computation of an oscillatory integral including $\operatorname{HeunC}$ function using Mathematica?

I am trying to numerically compute the following integral in Mathematica $$\int_{1}^{1000} dx \,(x+2)e^{-2Ia(x+2)}\operatorname{HeunC}[-4Ib,-4Ib,1+4Ib,1,-4Ib,-x/2]$$ where $\operatorname{HeunC}$ is ...
HadamardN2's user avatar
1 vote
1 answer
141 views

How to calculate the following expectation and variance?

Given $$X_1 \sim N(\mu_1, \sigma_1^2),$$ $$X_2 \sim N(\mu_2, \sigma_2^2),$$ $$X_1 \mathrm{\ and\ } X_2 \mathrm{\ are\ independent}.$$ and $$Y = \max(\max(X_1,0) + X_2, 0),$$ find $$E(Y) \mathrm{\ \ ...
Hayden's user avatar
  • 37
2 votes
1 answer
133 views

Zero equivalence in computer algebra systems

Testing whether an expression (say, on the real or complex numbers), with or without variables, is known to be difficult. There is an semi-algorithm by Daniel Richardson to solve it for the exp–log ...
Manuel Eberl's user avatar
-1 votes
3 answers
54 views

plotting a function i

How can i plot bellow function in MAPLE or MATHEMATICA or MATLAB? $$y=0.05+0.1\cdot e^{0.01x}\cdot \cos(0.2\cdot x)$$ while $x$ can be in the range of $ -350$ to $+350$ or less. Thank you
sepide shirazi's user avatar
0 votes
0 answers
217 views

Computational examples in differential geometry using Mathematica, Matlab, Maple etc. with visualization possible

I want to master the computing "apparatus" of differential geometry. Some theoretical sections are already very difficult to assimilate, and without visual calculations it is almost impossible to ...
ayr's user avatar
  • 731
0 votes
2 answers
177 views

General 2nd order ODE with non-constant coefficient

I'm trying to solve the general case of second order ODE: $y''(t) + p(t)y'(t) + q(t)y(t) = 0$. where $p(t)$ and $q(t)$ are polynomials divides contains some symbolic constant and $t$,$t^2$,$t^3$ and $...
Iftahnaf's user avatar
1 vote
0 answers
797 views

best way to plot the 3D shape made by many intersecting f(x,y,z) functions?

What's the best way to use a computer to plot the 3D shape made by many intersecting f(x,y,z) functions? I was trying to do something like the following, except I still have not idea what the shape ...
DiscreteMath's user avatar
1 vote
1 answer
170 views

If analytical solvers fail in solving an ODE, does it mean that it is unlikely have an analytical solution?

If analytical solvers (For example, Mathematica and Maple) fail to solve an ODE (Here, I have such situation with the ODE I have given in this question: second order ODE with time-dependent ...
Pojj's user avatar
  • 161
1 vote
1 answer
3k views

Analytical solution for convection diffusion equation

Convection-diffusion equation is: $\frac{\partial u}{\partial t} + \frac{\partial u}{\partial x} = 0.01\frac{\partial^2 u}{\partial x^2}$ Inital conditon is: $u(x,0) = sin(x)$ over the domain 0 to $...
AGN's user avatar
  • 215
1 vote
0 answers
206 views

Multivariate recurrence solve

I am currently working on a project and have reduced much of the problem to a single recurrence equation: $$g(x,y)=1-\frac{1}{6}g(y,x-1)-\frac{1}{2}g(y,x)-\frac{1}{3}g(y+1,x-1)$$ $$g(0,a)=1$$ $$g(a,0)...
Praneetmek's user avatar
0 votes
1 answer
64 views

How to define a funciton without the explicit defination in Maple?

I want to define a funtion in Maple like: g(t,r,theta,phi) but without the explicit defination. Thus, when I try to run diff(g,t) I hope it can give(only the formular, not(also it cant) the ...
Mr.CG's user avatar
  • 15
0 votes
2 answers
390 views

Maple and Mathematica disagree using dsolve for system of ODE initial value problem

I'm trying to solve a system of ODEs, symbolically, using Maple and Mathematica. I'm actually comparing the analytic solution with a numerical one (this is for a large simulation project, of which ...
buggaby's user avatar
  • 111

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