0
votes
0answers
6 views

How does one check function monotonity?

http://i.stack.imgur.com/JOS9o.png How does one analyze the monotonicity of $f(x)$? I know I need to use D[f[x],x] and check if it is >0 or <0 but NSolve is not ...
0
votes
0answers
19 views

How to get ContourPlot3D to run involving elliptic functions?

I need to plot zeroes of a function of three variables that involves elliptic functions. For example, I have ...
1
vote
0answers
10 views

Setting different B.C. for different fields in NDSolve

My question regards construction of a PDE solver for several fields, with different type of boundary conditions for several fields. Say I have the following set of equations: $$ ...
0
votes
0answers
9 views

Panel Regression in Mathematica

I need to do pretty much the most simple panel regression imaginable. I am working with a few variables. Some of them are random variables, so I am going to use a more traditional form of regression ...
0
votes
0answers
3 views

Gaussian process for machine learnig [migrated]

Here is my question in the equation 2.11 A is N by N matrix, so there is not feasible if N is large the textbook say in the euqation 2.12, we only need to invert size n by n. But I think K is 1 by ...
0
votes
0answers
9 views

Manipulate ListLinePlot for parameter definition out of scope

I would like to generate a ListLinePlot which data generated from the following functions: ...
0
votes
1answer
16 views

FourierTransform a function doesn't give result when variable is 0

I am trying to get a Fourier Transform of a function. However it doesn' work when the variable is 0. I used Mathematica 8.0 on a Windows Server 2008 R2 system. The code is as follows: Defining ...
0
votes
0answers
4 views

'Contingent' user interface (DialogNotebook with PopupMenus that depend on previous PopupMenus)

I'm creating a user interface for data entry. It makes sense for the content of certain menu items to depend on the information that has been entered earlier on the form. In a trivial example, ...
0
votes
1answer
21 views

insert comma between numbers

I have the following numbers rows and I want to insert a comma between the numbers? 6 7 9 51 64 68 79 102 116 128 148 155 184 202 273 283 292 1 7 8 10 52 65 69 80 103 117 129 149 ...
1
vote
0answers
12 views

Why are some of the isomorphisms not bijective?

Mathematica computes all the isomorphisms between graph g1 and g2: ...
2
votes
2answers
20 views

Find the Kimberling Sequence

How to find the Kimberling Sequence by using Mathematica? each row is obtained from the previous by boxing (and expelling) the main diagonal element, and then reading the first number after the ...
2
votes
0answers
23 views

Symbolic vector addition

I'm trying to figure out a nice way to add a mix of symbolic and explicit vectors/matrices without mathematica treating the symbolic vectors as scalars and promoting them to constant arrays. For ...
0
votes
0answers
14 views

How do I create a recursive tree plot for the Fibonacci sequence?

I would like to create a plot that shows the recursive tree for the nth number of the fibonacci sequence, as the one below. http://faculty.ycp.edu/~dhovemey/fall2005/cs102/lecture/fib5.png Ideally, ...
1
vote
1answer
29 views

Determine parameter from which on there is no more root for a given function

Let $\gamma>0$ be a real number and $\Phi(r)=\frac{1}{r}-\frac{\pi}{4}\left(H_0(r/2)-Y_0(r/2)\right)$ defined on $[0,\infty)$, where $H_0$ is the Struve function of order zero and $Y_0$ is the ...
0
votes
0answers
14 views

Putting constraints on interpolation

I am attempting to construct a function by interpolation, but I'd like it to be strictly increasing and convex. Is there an easy way to add constraints to Interpolation or should I change it further ...
-1
votes
1answer
20 views

Substitution in a power transformed in product

This could be thought as a duplicate question but it's in fact an extension of an old section. 1 + (a (α + β))/(b^2 + c^2) + ((α + β)^2 a^2)/(b^2 + c^2) could ...
0
votes
2answers
33 views

Maximum value of a function using loops

I have a function ab+bc+a/c, where a,b and c ranges from 1 to 5.I have to get an output of maximum value of this function and the values of a,b and c which give that maximum value. Is it possible to ...
0
votes
0answers
22 views

Exporting formatted numbers

I would like to format numbers of a list and write them in columns to file. ...
2
votes
1answer
48 views

Way to simplify an inequality with many variables

my problem is the following: I have three inequalities in five variables $x,u,a,b,c\in \mathbb{R},x>0 $: ...
0
votes
0answers
33 views

Motion of the particle on a surface

i have project for my studies. i must make plot3D my particle for z==Sin[2x] Cos[3y] and i must make surface for this model. But this surface must be Elipse and ...
0
votes
0answers
20 views

Mathematica does not responding

These days, when I opened mathematica 10.4 in Windows 10, I even cannot type three characters, and it stucks. Yes, every time when I type the third number or character, it stops. I found that, even, I ...
0
votes
1answer
38 views

Evaluate polinom with matrices

Let's say that I have the following polynom f = a+b+ab I want to evaluate this expression like this: ...
0
votes
0answers
44 views

Export animation from mathematica

I am trying to export an animation, but got an error.. The code is very simple, the combine function is a little complex: Export["combin.gif", combine] Here is ...
1
vote
1answer
45 views
-2
votes
0answers
52 views

Using “If” but get some strange results

I need to use "If" four times in part of my code, if it prints out "003 nh=50" then it might print "002 nh=100" and"001 nh=151", but it cannot print a second "003 nh=50". Or if it prints "001 ...
4
votes
2answers
272 views

Double integral

The question is Calculate the double integral where D is an area enclosed by the following lines, ,, and I have tried doing it the following way but its wrong and I cant seem to get it ...
1
vote
0answers
20 views

Express anonymous with formal parameters [duplicate]

I'd like to express the function F = Function[{#2[[1]] + #1[[2]]/#1[[1]], #2[[2]] + 1/#1[[1]]}] using explicit formal parameters. I've tried ...
-1
votes
0answers
45 views

DSolve an ITO process

I want to solve the following process: $$ dX(t) = \mu dt+\sigma dW(t) \\ X(0) = 0 $$ We know the solution is the following: $$X(t) = \mu t+\sigma W(t)$$ The question is how can I do it with ...
1
vote
0answers
32 views

extracting families with their representatives and number of repetition

There is a matrix: {{1,1,1},{1,2,1},{2,1,1},{-2,-1,-1},{1,1,-2},{1,-2,2},{2,1,-2},{1,-2,2},{-2,2,1},{1,2,2},{2,2,2}} How we can extract another matrix which ...
10
votes
1answer
118 views

Opposite of Alternatives in a Rule

Mathematica provides Alternatives, to match one of several patterns. In a rule, this is used as p1|p2|p3:>replacement. I ...
0
votes
1answer
61 views

Do not understand the result I'm getting from Solve [on hold]

I did Solve[k2 Cos[x] - k1 Sin[x] == 0,x] Since tangent is sin over cos, the solution must be arctan(k2/k1) But ...
0
votes
1answer
55 views

Lagrangian for Spring-Pendulum [on hold]

I solved a Spring-Pendulum System with NDSolve. I tried to plot a graph with the interpolated data but always returns a message "An improperly formatted directive with head Symbol was encountered." ...
0
votes
1answer
40 views

How to multiply two tensor with arbitrary ranks, on one index only (like GR)?

I am writing a function which take two tensors with the same dimensions but with arbitrary ranks and multiplies them over one index, just like this example from GR: See, I couldn't use ...
0
votes
0answers
14 views

Protected Variables in Parallel Loop

I am trying to run the code below. ...
13
votes
0answers
64 views

FindMinimum doesn't increase step size when necessary

I've spent much time finding a minimal example demonstrating this problem with FindMinimum. Normally one faces this problem when fitting very large and complicated ...
1
vote
1answer
26 views

Call multiple data sets in Listplot [on hold]

I am generating numerical data sets with a for loop and the table command. These data sets are named data[i], where $i$ is the counting variable of the ...
1
vote
0answers
28 views

Pattern intersection [duplicate]

Given a list of patterns {x, y, z} I want a pattern that matches if and only if each pattern matches. If instead of getting the intersection of patterns I wanted ...
0
votes
0answers
31 views

PDE: Specify AccuracyGoal, StepSize, and WorkingPrecision interval-wise

I am using Mathematica 8. I have two ODEs (in time) and a diffusion PDE (in radius and time) which are all coupled to each other. I solve them using NDSolve by ...
0
votes
1answer
17 views

Dynamically constructing symbolic tensors

Is there any way to construct tensor of any given dimension d and rank r with symbolic entries? i.e., instead of manually constructing one as Table[T[i,j,k],{i,1,10},{i,1,10},{i,1,10}] for d=3 and ...
3
votes
2answers
55 views

How to group this list in to some group whose element have a same number to relate

I have this list list={{0,7},{16,0},{16,2},{12,5},{11,1},{1,20},{3,20}}; This is my current method to realize it. ...
0
votes
1answer
38 views
0
votes
0answers
32 views

Rotation of basis system by WignerD

How can I calculate a 16x16 matrix HCF in a rotated basis system by applying WignerD. My basis is ...
2
votes
0answers
36 views

How does Context work?

I thought when we type a symbol without specifying its Context, it will search all the Context in ...
1
vote
0answers
29 views

How to draw an electric field without additional flux created in the middle of spreading from the charge?

I would like to draw an electric field. But from the condition of the electric field itself, the lines(or flux) should not be created again in the process of getting farther from the origin(or ...
0
votes
1answer
42 views

How to plot time-dependent vector field?

My problem is: plot the motion of the top of the vector $E$ (electric field) on the plane $$(k_1 - k_2)z = 0.25 \pi$$. Vector components are $$E_x = \cos(\omega t - 0.5(k_1 + k_2)z - 0.5(k_1-k_2)z)$$ ...
1
vote
2answers
48 views
3
votes
3answers
125 views

Epilog with multiple lists

I have as example multiple lists of x data (in mm) http://pastebin.com/7xwgGDsd which I want to plot against time (in sec). ...
1
vote
0answers
35 views

Lyapunov Exponent of the Rössler System

I would like to plot a semi-log plot of the Lyapunov exponent $λ_{x_0}, x_0=(1,1,1) \in \mathbb{R}^3$ versus time $t$, for the Rössler system described by: \begin{equation} ...
3
votes
3answers
145 views

How to show multiple points in Plot

I have data ...

15 30 50 per page