All Questions

60,007 questions
188 views

How to find 'n' nodes where all distances between them are greater than 'k'?

Consider the weighted graph 'net1': ...
43 views

Saving stored Solve output

my "lin" variable is a function of 2 variables: alpha and p1x. ...
144 views

EMF export bug v12

For some reason EMF vector image export deteriorates with every version. In v12.0 for Windows create a simple BarChart: x = Range@3 b = (BarChart[{x, x}] ) ...
19 views

How can I avoid typing the password again when I select a new remote kernel?

From the menu "Evaluation" -> "Kernel Configuration Options...", I can setup a new remote kernel, but I find it too much trouble to type the password again and again when I select a new remote kernel ...
34 views

Problem in solving an equation [closed]

It is giving me this error message, Solve::inex: Solve was unable to solve the system with inexact coefficients or the system obtained by direct rationalization of inexact numbers present in the ...
744 views

How can I use the Python library networkx from Mathematica?

Is there an easy way to access the Python library networkx from Mathematica? The improvements to ExternalEvaluate in Mathematica 12.0 should make this feasible.
37 views

GlobalSearch function

its seems I cannot run global optimization functions (GlobalSearch,GlobalPenaltyFn); The output is just a reproduction of input In[] = GlobalSearch[(x - 1.3)^2 + (y - 1.5)^2, {-x + 1, -y + 1}, {x -...
40 views

Getting named functions from an sequence of parameter values applied to a parametric function [on hold]

The general question is how can I loop on names and indices? An example: I have pfun = ParametricNDSolveValue[{y'[t] == a y[t], y[0] == b}, y, {t, 0, 10}, {a,b}] ...
37 views

How to export parameters in a text file?

I have some parameters defined in my notebook as, for example, a=1; b=2; c=3; and I want to export these parameters to a .txt file in which I have the following ...
30 views

How to Plot between square of the solution and square of the term occurring in the equation?

I am trying to plot between (mod[E01])^2 and (mod[as])^2 and for that using the following code as seen below. But not getting any plot. If anyone knows this, is welcome. ...
36 views

Admittedly, this will be a very naive question, but I'm really curious to learn how one can achieve the following in a simple manner: Suppose we have a text file formatted like so: ...
26 views

Plot labels disappearing

Using Mathematica 11.2 (Win 10), when the notebook containing the chart below is reopened the plot labels have disappeared. What's happening? ...
60 views

How to set HeavisideTheta[0] to 1 permanently

I always meet the HeavisideTheta[0] = 1 during my work, every time I need to use the function Replace[] to finish the job, which ...
24 views

GridLines using SciDraw

Does anyone knows how to include GridLines in Scidraw? I have looked up in the whole documentation and there is nothing related to it.
51 views

How to implement a Fourier series?

I've got a Fourier series (amplitude An and phase Phi, see below) 12 terms which I would like to implement in Mathematica. The ...
32 views

Save nested Solve results into variables (edited)

I have some solve results stored in the ptes variable: ...
56 views

Differential equation with polynomial powers

I'm trying to solve the following equation: Sin[f t] == y[t] + y[t]^3 + y'[t] + (y'[t])^3 Where f is a constant, the ...
159 views

3D rigid body physics engine

Is there a package in Mathematica that will allow me to simulate collisions of 3d rigid bodies? If not, what known libraries could I use and how? For example, one problem I want to simulate is a ...
44 views

Recursive Function in Multiple Variables

I can define a recursive function in one variable, e.g. defining the factorial function $f(n)= n!$ using Mathematica. But how do you do this for a function which depends not only on $n$ but on $x$ and ...
29 views

Christoffel symbols:The expression can't be used as part specification error

I'm a new user. I want to ask that what's the problem of my process? Can anybody teach me? I'm trying to calculate Christoffel symbols. ...
177 views

Mathematica 12 default graphic opacity is 0, i.e. invisible

I just upgraded to Mathematica 12 and am trying to draw a line in a graphic and am finding that the default opacity for a new notebook is 0, making them invisible. I can correct this for lines but ...
185 views

Mathematica 12, supported GPUs

It seems that Mathematica 12 doesn't support NVidia 2xxx (i.e 2080), 16xx or 1xxx series. Could it be that the CUDA section has not yet been rewritten for 12? https://reference.wolfram.com/language/...
23 views

Getting values of EllipticK with arguments that are very near 1

I need to evaluate EllipticK[m] very close to 1. However, when I get too close to 1 the function defaults to the exact solution for 1 , which is ...
29 views

Verifying which 5-strings form valid words

words = getWordsFromPi[200]; For[i = 0, i < Length[words], i++, if[DictionaryWordQ[StringJoin[words[[i]]], Insert[list, words[[i]]]]]] ...
47 views

Using ± to express two roots of a quadratic giving trouble [on hold]

the below equation are the roots of a quadratic I'm examining: $$A=\frac{r\pm\sqrt{r^{2}-\frac{4r(1+\alpha)(1-\alpha)T}{A^{s}}}}{{2r(1+\alpha)}{A^{s}}}$$ However, when I ...
39 views

Matrics manipulations

this is a basic question in Mathematica, I hope to get help to resolve it, How I can extract elements from matrics for example I have ...
63 views

Configuration of PlotLayout as “Row”/“Column”

A long awaited feature has finally been implemented in Mathematica v12: the multi-panel plots via PlotLayout! Demos are here: http://www.wolfram.com/language/12/...
49 views

How can I animate multiple objects at once?

I'm new to Mathematica and I'm trying to do this project where I have to animate multiple circles. I have 4 circles, each with x = 1, 2, 3, 4 , respectively. Each ...
30 views

Reversing axis prevents formatting of that axis

I'm looking to make a graph with the x-axis reversed and a frame and tick marks that are thicker than default. However, the x-axis tick marks do not maintain the specified thickness once I reverse the ...
41 views

Mathmatica solve one variable but no solution [closed]

solve[bx( 1 + ac ((x^(-0.5) - 1)/((1 - c)c^(-0.5) + c))) - d == 0, constant -> {a, b, c, d}, x] for some reason I don't get any solution? Please help. Thanks so much!!!
23 views

Discontinuities in taking the roots of a complex function

I have the following functions e1, e2, and e3 which consists of the functions ...
37 views

How can I select a solution that satisfies a particular set of conditions? [on hold]

I am solving a Kuhn-Tucker problem and the list of potential solutions is vast. I've been searching on these forums for a while and still cannot figure out a good way to select particular solutions ...
37 views

Axes behind plot lines

If I do a plot and want both the horizontal axis and a frame I can do this: ...
41 views

Generate a uniform distribution over an $n$-simplex employing quasi-random low-discrepancy points

This post is intended in a similar direction to an earlier one Can I use Compile to speed up InverseCDF? . I now wish to generate uniform points in an $n$-simplex (specifically $n=8$), making use of ...
34 views

Creating a directed random graph with negative assortativity [on hold]

How could I create a random graph that will have a negative assortativity? A graph where nodes with small degree will tend to connect to nodes with a high degree and vice-versa. Any ideas are much ...
59 views

Problem with fit

I am trying to find a proper matching function for the following data set: ...
33 views

Parallelizing nested for loops

I'm currently computing nested for loops. I count up a few counting variables and compute a value for each set of counting variables, then that value is added to an array. It is a way of adding up ...
35 views

Creating a prediction/distribution based on several years of data

So I have several years of data from a survey. For each year I've used FindDistribution and Predict to see if I can fit the data. Here's one example Where I used FindDistribution to get ...
25 views

Speeding up solving many coupled non-linear differential equations

I am currently working on a project that involves solving many coupled non-linear ODEs$^*$ I am using NDSolveValue and the time it takes to solve everything is (understandably) slow. But I was ...
23 views

Table with two functions to output matrix with values

So I have a wing modeled as an .STL and I am analyzing its structure so I need its cross sectional area and moment of inertia at points along its span. I do this by moving an infinite plane across the ...
47 views

How to solve an ODE system with Mathematica?

I I'm trying to solve this problem with mathematica but the code keeps giving me an error.
37 views

After saving (with QGis) the part of the map I´m interested in for a local visualization, I have the .zip file where you can see 5 files. I load the map in Mathematica with ...
36 views

Using Interpolating Function [duplicate]

I'm a bit of a noob with mathematica. I'm having a problem trying to use values from my solution. I've used ND solve to integrate ODEs. I have ...
406 views

How to prevent mathematica rounding extremely small numbers to zero?

I have a function that, while the maths itself is unimportant, at certain values it results in a very large number multiplying a very small number. E.g. 10^450000 * 10^-449998. As you can see, this ...
35 views

Solve: line and rectangle intersections

I have been trying to find the intersections between a rectangle and a line, following the example given in the Solve function: ...
27 views

Trying to solve recursion using rsolve

I'm new to Mathematica, and I'm trying to use RSolve to solve an equation I couldn't do in Matlab, as I got errors there too. This is the system I'm trying to solve:...
19 views

How to separate nested subexpressions to list?

I have an expression like this: 3*Subscript[v, 0]^3*Subscript[v, 1]^8*Subscript[v, 2]^7*Subscript[v, 3]^2 I would like to extract the exponents and put them into ...
18 views

Use ChoiceDialog to assign value to a variable within a function

This may be a routine answer that I have overlooked, but I am stumped... If I want to write a function using ChoiceDialog, how can I use what ChoiceDialog returns (true or false) to either set a ...