# All Questions

1answer
43 views

### Axis Labels Disappear With Manipulate

I have a ListPlot3D with custom axis labels that I am scrolling with Manipulate. My issue is that the axis labels scroll away as ...
1answer
75 views

### Is there a change in V10 with Solve and exponents?

I've encountered a strange problem with V10. I can't quite nail it down, but the Solve seems to be unable to solve equations that it could in previous versions. ...
0answers
62 views

### How to figure out whether a nonlinear inequality holds or not

I have an inequality consisted only of seven parameters as follows: $(1 + g)^{-(m+w)}\big[\big\{a+(1-a)(1 + g)^m\big\}(1 + p q)Q - (1 + g)^w \big\{(1 + g)^m (1 + q)-(1-p)q\big\} Q\big] < 0$ ...
1answer
39 views

### LibraryLink path problem

I have a library function that need to load some external data files. But it looks that the path in the default path of library function is the path that Mathematica is currently in. Is there a way ...
0answers
35 views

### Write equation as a multinomial in the variables x and Sin[y] and extract the coeficient of x*Sin[y]^2 [on hold]

I need help solving this problem. Thank you. (a*x^2 + b*x*Sin[y] + c*Sin[y])^2 + (a*Sin[y]^2 + b*x)^3 Write the above as a multinomial in the variables x and Sin[y] and extract the coeficient of ...
2answers
93 views

### Integrating Squared of Interpolating Function with respect to one variable

I am interested in evaluating a two dimensional interpolating function produced by solving the wave equation. Here is the code that includes the resulting interpolating function. ...
0answers
79 views

### Defining a Gaussian Distribution Fit to data

I am given a set of data and told ahead of time that the data will need to be fitted to a Gaussian Distribution. I know that Mathematica has preset functions for linear, quadratic, and cubic fits, but ...
2answers
46 views

### Write the equation as a polynomial in x and extract the coefficient of x^2 [on hold]

I need help solving this problem. Thank you. (a*x^2 + b*x*Sin[y] + c*Sin[y])^2 + (a*Sin[y]^2 + b*x)^3 Write the above as a polynomial in x and extract the ...
2answers
187 views

### Attaching a legend to BallAndStick picture

I am looking for a way to add a legend showing the identity of various atoms (with different colours) to this picture. Any Clues? ...
0answers
36 views

### k-means clustering in parallel

How can the k-means algorithm for some given distance function be implemented using ParallelMap or other parallel processing program constructs in Mathematica?
0answers
37 views

### k-means clustering using squared correlation in Mathematica

I am trying to cluster data using the squared correlation coefficient since in the case of my data, -1 correlation is equivalent to 1 correlation (polarities do not matter). How can this be done in ...
7answers
172 views

### Join decimal part

I have a list of mesures that each vector is like {0,1,-2,259} but it should be like {0.1,-2.259} So I did a rule, like ...
6answers
280 views

### Finding all paths of certain length between vertices in path graph, non-simple ones too

First I will tell you what my ultimate goal is, because maybe there's another way of doing it other than what I am trying. I need a list of all $(a_1, a_2, \ldots, a_N)$ tuples that satisfy certain ...
0answers
46 views

### How to make a new analytic function work seamlessly with Mathematica's analysis functions?

I am defining a new analytic function of six variables. I have algorithms to evaluate it numerically, and have amassed a large catalog of analytic properties. It is easy for me to program the ...
1answer
64 views

### Inverse prediction function

I am trying to write a code which learns a data set. Now, I want to know the input value for a given output value. Consider, the following code ...
1answer
42 views

### Convert Locator (x,y) values to Lat/Lon as per GetCoordinates on Map

I want to convert the (x,y) coordinates you get from using a locator on a map to Lat/Lon coordinates - exactly like the GetCoordinates tool does when you right click on a map. ...
1answer
66 views

### How to checkpoint computations?

Suppose I do some big experiment, presumably in a Table[], or a ParallelTable[]. Experience shows that there is a non-zero ...
3answers
111 views

### Combining more than two lists by first column as index

Please bear with me. It might be easy but its been hard for me. I have say three lists: ...
2answers
130 views

### Plotting an orbit using first principles [duplicate]

I am fairly new to Mathematica, but I am trying to plot an orbit of the Earth around the sun using the equation: $\quad r(t+dt) = (2 - G*M*dt^2/r^3)*r(t) - r(t-dt)$ I need to break this into ...
1answer
39 views

### Running a Mathematica Notebook from command line and saving the output [on hold]

I am working on a project that requires some calculations to be done in Mathematica. I don't know Wolfram language and I don't have the time to learn it (I am using a 30-day trial) so I have a python ...
4answers
104 views

### Precision problem with numerical solution of a differential equation

I want solve $$2\sqrt{|\gamma|}x = \int_{1}^{t} dy \sqrt{\frac{1+2|\gamma_2|y}{y^2(1-y)}}$$ where $0<t\leq$1. I'm using a for cycle to evaluate t, calculate the integral and the assign the $x$. ...
2answers
108 views

### Histogram with variable bin size [on hold]

Suppose I have some dataset,e.g., Histogram[RandomVariate[PoissonDistribution[2], 10000], 10] which gives, $\hspace{2cm}$ How can I change the histogram such ...
2answers
38 views

### Column Operation - Subtract part of nested list from part of another nested list [duplicate]

I have two lists with x- and y-coordinates with different z-coordinates of the form {{x0, y0, z0_1}, {x1, y1, z1_1}, ..., {xn, yn, zn_1}} and ...
1answer
70 views

### StreamPlot in Mathematica

A $2\times 2$ linear ODE system can be visualized by SteamPlot in Mathematica. For example ...
2answers
185 views

### Counting Real roots

I'm interested on how to count the number of real roots of a random polynomials in an instant, how to put the result in a table and how to plot it in a graph.I generated 1 million random polynomials ...
1answer
59 views

### Trouble to assign solution of differential equation to a function

I have written a function to Solve the following differential equation where the number n (called in my code Nphoton) is a variable. Nevertheless I have troubles to assign the solutions ...
1answer
55 views

### Taking the derivative of a function with indexed variables

I have a number of functions that depend on a variable x. I am using a second, integer variable to index these functions, i.e. something like ...
4answers
181 views

### Concatenating strings, unevaluated expressions and evaluated expressions/values

Maybe this is something very simple to some of you. Anyway, I think this can be useful to many others like me. I would like to build an output that involves strings, unevaluated expressions and ...
0answers
140 views

### Strange behaviour of MMA in derivatives of some standard functions

There are some peculiar things to be discovered in derivatives of some standard functions in MMA: Strange behaviour Example 1: Abs We have ...
0answers
49 views

### Listable on first level

I have some function which take List as input. f[l_List]:=someActions[l] I need apply this function to a list of lists. Now I ...
0answers
37 views

### Combining separate CHColorStructureDiagrams to form one molecular structure

I am trying to attach a fructose molecule to a sucrose molecule by using information obtained from the following ...
0answers
13 views

### How to calculate number of cards' permutations in card game [migrated]

I have trick taking based card game with 32 cards. Initially each player has 8 cards. After each trick number of cards in all players' hands are decreasing by one. I'm writing an AI Bot which knows ...
1answer
67 views

### How to get output from standard error in command line?

I'm trying to run some external command line program in Mathematica, and I have problem getting the output. For example, ...
3answers
188 views

### Speed of ConvexHullMesh

Pick $N$ random points on the surface of the sphere, then use ConvexHullMesh[] to compute their convex hull. Empirically, this takes time quadratic time in $N,$ ...
0answers
39 views

4answers
868 views

### Homotopy Visualization

I noticed that both the lower cased 'i' and the Apple logo  are topologically equivalent to the disjoint union of two closed discs. I'd like to animate a homeomorphism from the left to the right, ...
1answer
43 views

### ReadList or any other command to read in blocks of very large numbers

I have a data file, data.txt, having following data: ...
1answer
33 views

### How to use many global assumptions [on hold]

I would like to use many global assumptions. Say I have two global assumptions. $Assumptions = 0 < a < 1$Assumptions = 0 < b < 1 Then I would like ...
0answers
37 views

### Problem with importing numbers resulting from an executed file in Mathematica

I am running Mathematica 10 and I have a mathematica file, MBdebug.m, that contains the line val = Import["! ./MBpart1ep0", "Table"]; MBpart1ep0 is an ...
1answer
39 views

### Strange behaviour of Set and Part when given a sequence

Consider this example: lis1 = {a, b, c}; lis1[[2]] = Sequence[e, f]; lis1 (*{a, e, f, c}*) lis1[[2]] (*e*) lis1[[2]] = Sequence[g, h]; lis1 (*{a, g, h, c}*) It ...
2answers
48 views

### DSolve results not what expected

I have the following formula: s'[t] == 230.94 Tan[0.914743 - 0.138564 t] When I solve this by hand I get: ...
2answers
91 views

### Retrieving coordinate positions using ChemicalData for input to quanutm modelling software

I am trying to set up an input file for a quantum chemical modelling software. How do I obtain the (XYZ) coordinate positions in Angstroms using information obtained using ChemicalData. Have some ...
1answer
48 views

### Mesh for points in 3D

I've got a set of Eisenstein integers (triangle lattice points in the complex plane), and I've selected them to be above a line, so that they form a triangle: I then took these 2D points and ...
0answers
25 views

### Compiled DiagonalMatrix

The standard function DiagonalMatrix cannot be compiled, so I tried writing my own: ...
0answers
30 views

### gridlines in a plot [on hold]

Please, someone to help me to abbreviate this commmand ContourPlot[{x^2 - 2 y^2 == 1, x^2 - 5 y^2 == 1, x^2 - 10 y^2 == 1}, {x, -15, 15}, {y, -15, 15}, GridLines -> {{-15, -14, -13, -12, ...

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