0
votes
0answers
4 views

Entropy of lists and sublists

If we examine the following entropy outputs below, it can be seen that the entropy of {{a, b}, b, c, d, e} is not different from ...
0
votes
0answers
8 views

Plotting a partial sum

I am given the Legendre expansion of the first kind. $$f(x)=\sum_{n=0}^{\infty}A_{n}P_{n}(x).$$ I have worked the coefficient to be $$A_{n}\frac{1}{\left \| P_{n}(x) \right \|^{2}} ...
1
vote
0answers
29 views

Randomly generate a list of arbitrary length from a finite set [on hold]

I have a finite set of elements (5 to be exact). Suppose the first element has probability $\frac{1}{2}$ of being selected, while each of the others has probability $\frac{1}{8}$ of being selected. ...
1
vote
1answer
15 views

How to make all cells be displayed in TraditionalForm

I'm writting a test on mathematica, where most of the text is in Text style. I want that all cells be displayed as if I had gone to Cell>Convert to>TraditionalForm Display without having to do this ...
3
votes
0answers
30 views

Why is Reap result nested?

A minimal (toy) example for my question: i= 1; Reap[Do[Sow[i = (i + 1)^2], {4}]] (* {Null, {{4, 25, 676, 458329}}} *) I presume the entire result is a ...
1
vote
1answer
24 views

Find six vectors with rational entries under constraints?

Define six vectors v[i] with i=1,2,3...,6. Each v[i] is six dimensional and all entries in ...
2
votes
0answers
15 views

Manipulate strange behavior

Consider this simple code: Manipulate[n, {n, 1, 5}] When we evaluate it, we'll get Now try to click on the little plus sign to expand the controls. Suddenly ...
0
votes
0answers
18 views

notebook scrolling problem in 10.2: worse than ever? how to fix?

I use Mma notebooks to present in the classroom, so for me this is a serious problem. Before starting a class, I close all the sections, subsections, and subsubsections. During a lecture, I open ...
1
vote
0answers
18 views

Algorithm to determine if two colored graphs are isomorphic?

I have two (vertex-)colored graphs. I want to determine if they are isomorphic, with the condition that the isomorphism respects the colors of the vertices. Moreover, I want the algorithm to output ...
0
votes
0answers
21 views

Proof bu induction? [on hold]

I've been stumped on this for a while, and even had a EE PhD take a look with no joy. show that for any n >= 2, the following formula is valid: 1^2 - 2^2 + 3^2 - ... + (-1)^(n-1)n^2 = ...
2
votes
0answers
25 views

ListPlot3D: generating mesh lines at hard-coded locations

I am plotting a surface specified with a set of {x,y,z} coordinates with ListPlot3D. This data set surface does not extend ...
0
votes
0answers
27 views

Solve a function to find the optimum value of parameter in mathematica

I have a complicated function as shown It doesn't have a standard integration as far as I know. Now, numerical integration of the left hand side function over a set of points gives the right hand ...
1
vote
0answers
35 views

Unix 2 way communication while running M on Windows

Mathematica for Linux I've found to be to filled with bugs, so I'm looking to workaround the issue by running a Linux virtualmachine inside of a Windows host. It is possible to create a two way ...
8
votes
1answer
45 views

How to share a notebook?

I have a folder in dropbox syncing to my desktop. I tried sharing a notebook file this way, but this generates lots of errors, conflicts, and data loss: I have notebooks with Dynamic and other ...
-1
votes
0answers
28 views

When f(x,y) can be expressed as g(x)h(y) [on hold]

Under what conditions can f(x,y) be expressed as g(x)h(y) ? What can be the proof of this ?
1
vote
1answer
30 views

Propagation of error for not-analytical calculable inverse function

I have the function: gcsymb[Lpd_,a_,c_]:=1 /finv[1./Lpd^2,a,c]/Lpd with the definiton of finv: ...
4
votes
0answers
37 views

Expanding PolyGamma function error

For large half-integer arguments of PolyGamma[] function the FunctionExpand[] or ...
3
votes
4answers
247 views

Minimal overlap area of circles

I have 20 points in the 2D plane with $(x_i,y_i)$ coordinates. I want to use Mathematica to optimally distribute 10 circles with equal radius of a given positive value $R$, i.e. to determine with the ...
1
vote
0answers
44 views

Legendre expansion of functions [on hold]

I am given the expansion for the Legendre function of the first kind. It is just $$f(x)=\sum_{n=0}^{\infty}A_{n}P_{n}(x).$$ I have found the expression for the coefficient $A_{n}$. However I would ...
2
votes
1answer
62 views

Calculate sum of probabilities in multinomial model

The question at hand: On average in every 7th chocoloate egg there is a figure to be drawn from a known list of special figures (e.g 15 distinct pieces) the other draws are on average fails. With ...
0
votes
1answer
47 views

Global variables [on hold]

I have a workbook I am writing, there are 2 cells in it and then each cell is divided into sub cells. At the top of the first cell i made a bunch of variable assignments such as length=10, x=6, d=4, ...
0
votes
0answers
41 views

How does KalmanEstimator update the Kalman gain, process noise and state variable mean?

The first "Application" in the documentation for KalmanEstimator is copied below with additional variables for clarity. ...
2
votes
0answers
40 views

We need to know the input signal when we use KalmanEstimator?

The first "Application" in the documentation for KalmanEstimator is copied below with additional variables for clarity. ...
3
votes
0answers
28 views

What does OutputResponse[sys, { {u1,u2,u3}, {v1,v2,v3} } ] do?

I am puzzled by the result of OutputResponse[sys, {{u1,u2,u3},{v1,v2,v3}}]. OutputResponse is used this way in the first "Application" in the documentation for ...
2
votes
1answer
228 views

What is wrong with FindRoot?

I am trying to find a numerical solution to the following transcendental equation ...
1
vote
0answers
16 views

Open file menu bug with ubuntu dark theme [on hold]

I'm using Ubuntu with a dark theme and the navigator on the open file menu is now with a white background and white letters. Is there a way to fix this?
2
votes
0answers
25 views

WSTP/MathLink: Transfering long lists (that require 64bit for index range)

I am using WSTP to call external C-Code from a Mathematica 10.2 session on a Linux-x86-64 system. The routine WSGetReal64List(WSLINK link,double **a,long *n) seems ...
0
votes
1answer
41 views

Strange Simultaneous Equations [on hold]

Solve the simultaneous equations: 70-T=7a T-40=4a By multiplying both sides of the equations by a factor and shifting the terms I transformed them into the following form: -28a-4T=-280 ...
0
votes
0answers
34 views

Problem with 3D plots window crashed

My mathematica7 window in fedora21 crashed when 3d plots are rotated without any warning message. I checked webpages for any solutions and found one answer. I followed it typing mathematica -mesa ...
0
votes
0answers
63 views

Time zone Projection [on hold]

This question stems from another question at here. I want to compare time zones (civil time) with watch readings from a model clock (see illustrations in link above) using this theory. I'm not ...
11
votes
1answer
97 views

How to restore corrupted files?

I have a file that I can't reopen because MMa was "Not Responding" and I had to shut it down. I found links online to this: http://support.wolfram.com/kb/12423 I executed those two instructions in a ...
1
vote
0answers
39 views

How to avoid “Quit[]” to execute notebook multiple times [duplicate]

I am using a program to binarize several images and then adding all the images together using "ImageAdd" to get one image. This image is required for further analysis of the images. The program ...
3
votes
1answer
90 views

EquationTrekker using Mathematica 10.2

I wonder whether the problem that arise with the following code is specific to my machine, as it seem to work with the documentation example. ...
3
votes
2answers
144 views

Looping through 3 million elements of a list to 'Set' values is slow [on hold]

I am looping through the 3 million elements of a time-series (v1, o1) and corresponding values (v2, o2). v1 contains a uniformly increasing timestamp (e.g. 1 to 3,000,000 in increments of 1) o1 ...
0
votes
1answer
50 views

Problem with mathematica plot 3d [on hold]

u[x_, t_] := (x - t)*e^(-(x - t)^2) u[x, t] Plot3D[u[x, t], {x, 0, 5}, {t, 0, 5}, AxesLabel -> {x, t, u}] I get an error Plot3D::exclul: {Im[e]-0} must be a ...
0
votes
0answers
24 views

Problem with mathematica code [duplicate]

Plot3D[u[x, t], {x, 0, 5}, {t, 0, 5}, AxesLabel -> {x, t, u}] I get an error Plot3D::exclul: {Im[e]-0} must be a list of equalities or real-valued functions. ...
6
votes
1answer
78 views

Extracting fit weights directly from a FittedModel object

Suppose I have the following data: ...
3
votes
0answers
41 views

What are all the elements of the expression returned by KalmanEstimator used for?

The first "Application" in the documentation for KalmanEstimator is copied below with additional variables for clarity. ...
-3
votes
1answer
48 views

How to sort my list? Help [on hold]

I have a list={1,2,3,4,5,-6,9,3,12,0,-3}. I want to sort its, as way {even,odd,even,odd,....}. Moreover in crescent way for even and odd numbers. So the result ...
2
votes
1answer
85 views

Eigenvectors of numerical matrix

I have a large numerical matrix whose eigenvalues are all distinct. In the documentation for Eigenvectors it says: For approximate numerical matrices m, the ...
2
votes
1answer
51 views

Plot using a list of variables

I have the following code: ...
4
votes
2answers
84 views

FunctionInterpolation and Which combine badly

Update: The main question has been answered, but my problem hasn't been solved. The problem is I have a situation where I want to use Which on an InterpolatingFunction several times to repeatedly ...
3
votes
0answers
60 views

NSolve doesn't work on an equation containing a numerical integral and constraints

I'm having trouble getting Mathematica to solve equations numerically. I know that its important to specify the type of variables for pattern testing (see e.g. here) but this doesn't seem to work. ...
0
votes
1answer
75 views

Special fractions generator

Note that 13/33, 1313 / 3333 , 131313 / 333333, ... They are always equivalent fractions Fraciones generate desire to have this property based arbitrary ...
4
votes
3answers
237 views

Constructing Tri-Diagonal Matrices

Fractional Calculus Course, we are instructed to create an $n \times n$ Tri-Diagonal matrix in the form of: \begin{array} a A &= \begin{bmatrix} 2 & -1 & 0 & 0 & ... ...
5
votes
1answer
96 views

Finding planetary conjunctions with Mathematica (project-level)

Summary: What's an efficient way of finding planetary conjuctions with Mathematica using the SPICE kernels, and without using AstronomicalData (which I believe is less efficient). NASA publishes ...
6
votes
3answers
127 views

Fitting data with interdependence

I have an issue, of which I'm not sure it can be solved, with or without Mathematica. I feel as if it should be possible, but I'm quite clueless as to how. Some introduction is required. I'm working ...
0
votes
0answers
7 views

Lychrel number Algorithm [migrated]

Recently became fascinated with the search for Lychrel and palindromic numbers as recreational mathematics. for the who are unaware, the process for performing this check on a number manually is as ...
-2
votes
1answer
70 views

Are these codes the same?

I have this code: ...
7
votes
2answers
128 views

ListLinePlot Filling Wrong

Bug introduced in 8.0 or earlier and persisting through 10.2 or later. I used ListLinePlot to plot data from .csv files. However, the y-values from Graph 1 do ...

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