The tag has no wiki summary.

learn more… | top users | synonyms (2)

14
votes
1answer
219 views

Mathematica 9 cannot solve a difference equation that Mathematica 8 can

Consider RSolve[{a[n + 1] == 2 a[n] + n (1 + 2^n), a[1] == 1}, a[n], n] Mathematica 8 can solve this quickly, but Mathematica 9, even after being allowed to run ...
9
votes
1answer
315 views

Is it possible to find a limit of a sequence given by its recurrence relation?

I need to calculate a limit of a sequence given by its recurrence relation. I tried the following: ...
5
votes
3answers
237 views

How can I solve a forward-backward-looking recurrence system?

I would like to (numerically) solve a forward-backward looking recurrence equation in Mathematica. The system is something like: ...
5
votes
1answer
150 views

RSolve[{y[0] == y0, y[t + 1] == (1 - (t + 1)/100) y[t]}, y[t], t]

When I evaluate this code: RSolve[{y[0] == y0, y[t + 1] == (1 - (t + 1)/100) y[t]}, y[t], t] I get an RSolve::bvnul error. I don't understand why. Yet, if I ...
4
votes
1answer
405 views

RSolve Lotka-Volterra: A Closed Form Solution to this Difference Equation?

I would like to solve a difference equation, a Lotka-Volterra difference equation. I tried a model from http://www.stolaf.edu/people/mckelvey/envision.dir/nonDE.lotka-volt.html Using their ...
4
votes
4answers
216 views

Can I generate a “piecewise” list from a list in a fast and elegant way?

Suppose we have a number list a: n = 1000000; a = RandomReal[{0, 1}, {n}]; We want to generate a list ...
4
votes
1answer
108 views

RSolve gives a Context::ssle error

I want to solve the following recurrence equation RSolve[{(k + 2) c[k + 2] q^(k + 1) - c[k] == 0}, c[k], k] During calculation in Mathematica I get this ...
3
votes
2answers
304 views

RecurrenceTable with a recurrence function of two variables

I have to calculate the cool down process of a regenerative heat exchanger. I solved the problem in Excel before, but now I want to do it with Mathematica. I want to create a table with the variables ...
3
votes
2answers
168 views

RSolve with assumptions

I want to solve the following non-linear first order difference equation: $$ k_{t+1} = (1-a) k_t^{a} $$ with $0 < a < 1$, and $k_0 = \text{const.}$ . Of course, the solution is easily found, ...
3
votes
0answers
56 views

How to combine DifferenceRoot objects for odd and even-indexed terms

I'm trying to analyze a certain infinite sequence $S$, indexed by positive integers starting from $1$. It can be split into two subsequences: $S^{odd}$ by removing all even-indexed elements and ...
2
votes
2answers
134 views

Rook walk and RecurrenceTable in Mathematica

This appears in a combinatorics book: $a(m,n)=2 a(m,n-1)+2 a(m-1,n)-3 a(m-1,n-1)$ It is a recurrence equation for the number of rook walks from $(0,0)$ to $(m,n)$. The initial conditions are: $ ...
2
votes
0answers
85 views

RSolve and incomplete gamma function

I am interested in how Mathematica uses the incomplete gamma function to solve difference equations. For example, if we have this inhomogeneous, 2nd order equation and use ...
2
votes
0answers
186 views

Nonlinear recurrence relation

I entered the following recurrence relation into RSolve and it just gave the question back to me. $$a_{n+1} = \frac{(1+a_n +(a_{nāˆ’1})^3)} 3$$ Is there another way to get a formula for the nth term?
1
vote
1answer
120 views

MAP a business cycles model

There is a Business Cycles Map on Phaser 3.0 and I've trying to run it on Mathematica the last four days without succes. The equations are $$ x_1 = (1.0 - a s)x_1 + a \left[s m + g \left(\frac{s ...
1
vote
1answer
56 views

Limit as n -> āˆž for RSolve with Multivariate Recurrence Relation

I'm trying to solve the following when n -> āˆž: ...
1
vote
0answers
58 views

RSolve: Errors while solving Partial Difference Equation

I tried solving following partial difference equation in Mathematica by typing ...
0
votes
1answer
121 views

I don't understand ListCorrelate! [closed]

I want to solve a PDE equation (like Schrodinger equation) using finite difference in Mathematica. I don't understand what this code does! ...
0
votes
4answers
132 views

RSolve fails on a two-equation non-linear system

I have a system of just two recurrence equations, I need to solve them and so I use RSolve: ...
0
votes
1answer
79 views

Recurrence equations with periodic coefficient

Suppose I have the following recurrence equation: $$ F_{i+1}P_{i+1}+F_iP_i-P_{i+1}+P_i=2J\,, \quad\textrm{with}\quad F_{i+L}=F_i,P_{i+L}=P_i\,. $$ $J$ is constant, $\{P_i\}$ are probabilities with ...
0
votes
1answer
102 views

Explicit, closed formula for recursive integral as a function of the recursive parameter

This is a follow-up of this question/answer. I'm working on a recursive integral more complicated than the one on the linked question, but this one can be used as an example. I would like to obtain ...
0
votes
1answer
54 views

FindRoot finds a solution not found by NSolve

I am trying to solve a polynomial equation of higher order with non-integer exponents. When the order of the system is greater than 4, FindRoot provides a correct solution that is not found by NSolve. ...
0
votes
3answers
63 views

Recurrence Relation construction [closed]

How can I go about setting up a recurrence relation where the first 10 values are a constant and the second 10 values are another constant? Ideally, I'd like an efficient way to set ...
0
votes
1answer
57 views

Start indexing at 0 for RSolve without giving an initial value [closed]

I am trying to use RSolve with indexing beginning at 0. Whenever I enter a basic command such as to solve a difference equation such as $a_{n} = 2a_{n-1} + 1$: ...
0
votes
2answers
185 views

Random variates in Recurrence Function

I'm completely new to Mathematica and can't seem to find an answer elsewhere so hopefully I can get some help here. I'm trying to plot a recurrence relation, where a random variate is generated at ...
0
votes
0answers
43 views

Calibrating a difference equation system

Sorry for not posting it in the first attempt properly. Consider the simple problem of a first-oder difference equation: ...
0
votes
0answers
52 views

RSolve? How do I Solve these equations using Mathematica

How do I solve these using Mathematica? I'd like to have formula for p[2] to p[n-1]. P[j] ...
0
votes
0answers
31 views

Green functions for recurrence equations

Is it possible to solve recurrence equasions in Mathematica with the use of Green's functions and get a solution as a series?
0
votes
1answer
249 views

Solving recurrence relationship using iteration

I am trying to create a Mathematica function that basically splits up a continuous function (in this case a physical potential) into steps (strips as it were) and returns the value of the function at ...
0
votes
0answers
66 views

RSolve and “the given boundary conditions lead to an empty solution”

I am trying to solve the following recurrence relation: ...
0
votes
0answers
89 views

Hahn-Exton q-Bessel's function in Mathematica

I am interested in implementing Hahn-Exton's q-Bessel Function of the first and second kinds, $J_\alpha^{(3)}(x;q)$ and $Y_\alpha^{(3)}(x;q)$ , in Mathematica. There's no difficulty in defining the ...
0
votes
0answers
419 views

Solving coupled eigenvalue differential equations

I am trying to solve an equation of the form as follows $\left(\begin{array}{cc} -\frac{\hbar^{2}}{2m}\frac{\delta^{2}}{\delta z^{2}}+\sin^{2}\left(z\right) & z\\ z & ...
-2
votes
1answer
136 views

Proof: Convergence of an equation and show the first derivative is bounded

We have the following equation \begin{equation} x(k+1)=\arccos\bigg( -\frac{1}{2(Dr^{\frac {|\sin(2x(k)+\theta)|}{M\sin x(k)\sqrt{A+2B\cos(2x(k)+\theta)}}}+1)} \bigg) \nonumber \end{equation} ...