2
votes
0answers
278 views

NDSolve Issue with initial conditions

I am trying to implement a Poincare section for a gravitational movement on the plane $(x,y)$. Here is the code I wrote ...
2
votes
1answer
85 views

Illogical failures of symbolic integration over Boole

Is there a way to work around integration over Boole being mysteriously flaky like examples show below? Is there a meaningful explanation for this behaviour? ...
2
votes
1answer
248 views

how can I solve integrals including recursion of some sequences of functions

I would like to solve the equations as given below in mathematica. I have written some codes before but I have no idea when there is sub indexing to indicate the series of functions. I will be very ...
5
votes
2answers
220 views

How to get complement of a pattern

I have a list. I want to get all the elements in that list which do not match a given pattern. That is, I want the strings which do not match any of the following patterns: First and last characters ...
3
votes
2answers
157 views

Using list elements in TrackedSymbols for Dynamic

During the execution of the following code a column of three lists and two sliders are displaying in output. The first list updates if either a or b changes. The second list updates only if the value ...
24
votes
4answers
540 views

obtaining random element of a set given by multiple inequalities

I try to obtain random elements from a set given by multiple inequalities. This is of general interest to me, but let me present one example here: I have multiple inequalities specifying half spaces ...
0
votes
2answers
253 views
4
votes
3answers
95 views

Creating a function after working out an example calculation

I have created this setup, it is giving me the correct answer, however I am interested in a function that does all this calculations and creates a output of mean and standard deviation. The function ...
0
votes
2answers
655 views

How to input a 3-vector in spherical coordinates?

I would like to input a 3-vectors in spherical coordinates $(r, \theta, \phi)$ and be able to operate on such vectors (dot and cross product) with the results being given in the same spherical ...
3
votes
0answers
104 views

Package for interacting with the AR.Drone by Todd Gayley?

Anyone in possesion of the package develop by Todd Gayley to interact with the AR.Drone? Haven't been able to find it anywhere... Referring to this video: ...
2
votes
1answer
722 views

Nonlinear least squares

I have a typical nonlinear least square problem and it seems very similar to the example provided in the section on parameter fitting at the Wolfram website. Unfortunately I always get some error ...
0
votes
1answer
128 views

Order of evaluation in nested expression

I am trying to make a function that works as follows: Integrate 1 for all t in the interval $ [0,1] $ such that the first element of function vstar is positive. ...
3
votes
3answers
171 views

Properly ordering the output of FileNames for a directory consisting of files with consecutive integer names [duplicate]

Say I have a number of files in a directory at some location (C:\dir1\dir2\dir3...), and I pull an array of strings corresponding to the file names with the command: ...
3
votes
1answer
126 views

Saving a text file with an unknown extension

I need to export a file with the extension .mac (short for macro in an external program), though it is essentially a text file (saving .mac in Microsoft notepad works fine). However if I try ...
10
votes
1answer
690 views

Roads network visualization by thickness and color intensity by population from GIS files

We can have road networks of the countries in GIS shape file.For exmple from here. Normally traffic flows are proportionate to populations of the cities. I wonder how we can have the same in ...
4
votes
2answers
273 views

How to use SuperLog by loading SMLE.m

I am researching a software reliability model that has many parameters that need to be estimated. I want to use a maximum likelihood estimator (MLE) to estimate those parameters. After I searched ...
2
votes
0answers
135 views

I am not able to plot legends in list density plot using c program. Getting blank legend

I have tried to load the "PlotLegends'" package. Here is my code, ...
2
votes
1answer
178 views

How to combine multiple Graphics3D scenes into a single Graphics3D scene?

ProteinData["A2M", "MoleculePlot"] gives you a Graphics3D object below. I'd like to display multiple of these proteins in a ...
6
votes
1answer
231 views

Behavior of Graphics`Mesh`InPolygonQ with self-intersecting polygons

Playing around with some of the answers in the question How to check if a 2D point is in a polygon? I noticed that: Graphics`Mesh`InPolygonQ[poly,pt] Displays ...
1
vote
1answer
166 views

How can I reproduce some surface plots in Mathematica?

I am not really familiar with Mathematica. I wonder if some one can help me draw any of the following surfaces. I will be appreciative if you tell me how to use equations and ...
12
votes
2answers
344 views

Color Histogram3D by Bin Location

I am using a Histogram3D plot to view the correlation of the R & G of an RGB image. Naturally, I want the bins to have a color corresponding to their $x$, $y$ ...
1
vote
0answers
62 views

Convert ImageSize to FieldSize [duplicate]

How might I construct a function called EmToPX[p] such that the following 2 InputFields would be the same width. If not please ...
3
votes
2answers
594 views

FindFit for a differential equation model with multiple variables?

I'm trying to figure out how to use FindFit with a multivariable differential equation model and data. I've successfully made it work for the one-variable version ...
0
votes
1answer
132 views

Plotting blends of colors over lists of lists in 3D

I have a list of lists containing spectral data, many thousands of points long. Each sublist contains 13 parts, and I need to plot them in 3D with a blend of RGB colors derived from the spectral ...
1
vote
0answers
61 views

How to take the log of an equation? [duplicate]

I am researching a software reliability model that has many parameters that need to be estimated. I want to use a maximum likelihood estimator (MLE) to estimate those parameters, but my model is too ...
9
votes
4answers
894 views

Plotting an epicycloid

I am fairly new to Mathematica and I cannot figure out how to plot an epicycloid. I have plotted some neat looking things in my attempts, but can't make one. I am not looking to make an animation, ...
0
votes
1answer
164 views

Solve doesn't return all solutions [duplicate]

I got a simple cubic equation as input, but Mathematica does not give all solutions, why is this the case here? ...
9
votes
1answer
436 views

ParallelEvaluate for function minimization

Is there a parallelized version of a minimization routine available in Mathematica? The objective function is non-linear and the gradients have to be numerically computed. Every function evaluation ...
7
votes
1answer
207 views

Name of current Notebook

I've searched the documentation, this forum and with google, but I was not able to find how to ask Mathematica to give back the name of the current notebook file one is working on. Perhaps something ...
7
votes
1answer
279 views

Is it possible to construct a topological map of road network of Bangalore?

I saw this example wherein the CityData gives the map of a city. But this is available for a relatively small set of curated regions. Is it possible to extract ...
0
votes
0answers
126 views

How does Mathematica solve eigenvalues?

I believe mathematica uses some techniques beyond our book. According to the text book it is not possible to solve eigenvalues of which the matrix has not completely eigenvectors, or of those matrix ...
2
votes
1answer
198 views

ParametricPlot3D[] Question

I know this is very similar to a previous question I asked, but there are some differences. When I graph: ...
6
votes
2answers
436 views

Export notebook to pdf in landscape orientation

Assuming the following is a notebook with a linebreak: How might I export a landscape pdf (preferred although other formats could work) such that each cell content each group of cells above and ...
1
vote
4answers
236 views

Calculating the median difference between elements with a (particular pair) of consecutive integer indices residing in the same sublist

NOTE: I formally made a serious mistake in the first example provided. pointLists[[1]] had an extra element, and we should have a guarantee that ...
4
votes
2answers
381 views

How to exclude some points to make them more evenly distributed in a figure

If there are some points in a figure, how can I exclude some points to make them more evenly in the figure? 'Evenly' here can be defined as the number of points in each $0.01*0.01$ box is at most one. ...
4
votes
4answers
551 views

Replace For-loop with functional code

I am very new to Mathematica. I have code written using for loops. I want to rewrite it using Map/Thread but I am not sure how ...
3
votes
6answers
161 views

Change sublist based on position

Supposed that: list = {2, 3, 5, 7, 9}; sublist = {{3, 3, 5}, {2, 2, 2, 7, 9}}; I want to change each sublist in sublist as following: Find the positions of ...
4
votes
0answers
195 views

Memory problem with producing complex graphics of general type

The problem I am about to ask has appeared once here: Memory Leak in Frontend - anyone know a workaround?. However, in this question I would like to put it in a bit different context. Problem recipe: ...
5
votes
1answer
733 views

All possible topological orderings of a graph

TopologicalSort[] returns one of many unique orderings. From wikipedia: if a topological sort does not form a Hamiltonian path, the DAG will have two or ...
1
vote
1answer
150 views

Minimum value with two factors

Approximate the minimum value of $2e^{x-2}-6x+xe^{x-2}$. Is my input correct? If not can you please correct it? ...
6
votes
1answer
257 views

Intersection of two functions in SphericalPlot3D

How do I draw the intersection of these functions? ...
6
votes
1answer
521 views

Issue with NSolve

I defined the following function: sw[ θ_, ϕ_, h_] = 1/2 Sin[2 (ϕ - θ)] + h Sin[ϕ] Based upon whether I use Solve or NSolve, ...
10
votes
1answer
448 views

Why does Mathematica return a Fourier transform for a function for which it is not defined?

The following function $$g(x) = (1 + x^{1/a} )^a $$ should NOT have a Fourier transform, as far as I am aware, for any real values of $a$ since $g(x)$ is not nice in the sense of decays quickly ...
1
vote
1answer
675 views

How to plot a polygon and a line on the same graph?

I have to plot the line 1 + 4 t, 2 + 5 t, 1 + 12 t and the polygon with points {2, 3, 4}, {1, 4, 5}, {3, 3, 3} in the same graph to see if the line goes through the polygon. I was able to get them to ...
1
vote
3answers
129 views

Replace inside a Held expression separate context

How do I replace content inside a Held expression without local values coming through? For example if you run the following code you get g[2] instead of ...
21
votes
3answers
2k views

Is there something like DensityPlot3D to visualize atomic orbitals?

I'm visualizing some hydrogen like atomic orbitals. For looking at plane slices of the probability density, the DensityPlot function works well, and with something ...
1
vote
1answer
479 views

Coloring Bifurcation Diagram

I have the following Pitchfork bifurcation: f[x_, r_] := r x - x^3 I was able to find some nice code on this site to draw up the Logistic Map. I have the ...
3
votes
1answer
291 views

Define operator algebra

My objective is to work out commutators like this $$[f(x,y)\partial_x^2+g(x,y)\partial_x+h(x,y),a(x,y)\partial_x^2+b(x,y)\partial_x+c(x,y)]$$ or ...
6
votes
3answers
203 views

Can't force UnitConvert to be evaluated in Plot

I'm trying to use new units support in Mathematica 9. When I Plot Quantity functions everything is OK. ...
0
votes
1answer
148 views

How to get the coordinates of the point that the mouse touch?

How to get the coordinates of the point that the mouse touch? When my mouse touch the picture that the Mathematica touch ,I hope it can return the coordinates?

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