1
vote
0answers
25 views

Ignore $MinPrecision when using Print

I have a function that contains a For loop and sometimes takes several hours to run. It's important that I keep a high precision, and I insert ...
0
votes
1answer
174 views

How to put legends in a chart plot [closed]

How can I put a chart legend inside a bar chart? I tried Placed[ ... ,{Right,Top}], but it didn't work. It works for Plot. ...
0
votes
1answer
64 views

Implementation of a Hanning filter

I'm implementing a package for in-house signal processing. I wrote here a quite trivial function implementing a Hanning windowing of the signal. ...
5
votes
2answers
132 views

How to select specific subvalues from a function definition

Consider: h[1][tag1] = 1; h[1][tag2] = 2; h[2][tag1] = 3; h[2][tag2] = 4; Is there a fast way to obtain downvalues for only h[1], or h[2]? For example ...
1
vote
0answers
122 views

How to make Layer Directed Graphs (LDG) in mathematica?

I am wondering if I can make a graph like that somehow: I am new to mathematica, I tried to play with Creating a graph with variable size of vertices and variable thickness of edges . I figured if I ...
1
vote
0answers
46 views

workbench: how to extract a piece of code into a function

For example assume that the following code is given f[x_, y_]:= Block[{a, b}, a = Sin[x]; b = Cos[y]; c = a + b ] and I want to change it ...
2
votes
1answer
172 views

Issue in displaying a rotated PolarPlot with Show

I can use PolarPlot to generate a plot; however, I would like to rotate the plot by 90 degrees and then output the result using Show. Here is the code ...
1
vote
0answers
40 views

How to find discretezation error of NDSolve

Is there a way to find out how large the truncation, round-off, and other errors that occur from discretizing a differential equation are while using the default settings in NDSolve? Or would I have ...
2
votes
1answer
85 views

How to create .ico file in Mathematica?

How to create .ico file in Mathematica? I mean the favicon images used for web sites. Directly using Export["file.ico", <some graphical expression>] does ...
26
votes
3answers
10k views

Marking points of intersection between two curves

I'm trying to illustrate the solutions numerically and graphically for an equation such as Tan[x] == x. I think I did everything ok except I wanted to mark each ...
0
votes
2answers
131 views

How to do symbolic definite integral without copy and paste the intermediate results?

I am do a symbolic definite integral, I am doing it like this: Integrate[1/Sqrt[(ϵ + u)^2 + Δ^2], ϵ] // FullSimplify It gives an output: ...
5
votes
5answers
396 views

Joining some strings in a list of strings

So, say I have a list of strings, representing lines in a file, like so: ...
1
vote
1answer
219 views
1
vote
0answers
116 views

ExpToTrig transforms solution to 4th order ODE into unwanted form

Mathematica gives the solution of the second order differential equation DSolve[a y''[x] + b*y[x] == 0, y[x], x] in trigonometric form ...
0
votes
1answer
124 views

Plotting two-variable function as function of one variable with manipulate for both variables

I have a function g(x,y) and would like to plot it as g(x) with a slider to vary y. What I currently have is a g(x,y) plotted as g(x) but with y as a parameter which I can adjust: ...
0
votes
1answer
111 views

Normalize equation in NDSolve?

I have numerically solved and plotted the solution to the Mathieu equation using NDSolve successfully, as below: ...
4
votes
1answer
104 views

Dial control for Manipulate?

I'm trying to make a control item in a Manipulate that is a simple dial. I'm trying to mimic Manipulate[theta, {theta, 0, 360}], ...
0
votes
1answer
670 views

Plot not working

I am trying to generate a plot for S2[w]. My code is below ...
0
votes
1answer
146 views

Sorting lists of lists with string elements [closed]

I have a list of sublists. One element of each sublist is a string element. For example: list = {{1, "banana", 3}, {3, "orange", 1}, {2, "apple", 2}}; When I ...
0
votes
1answer
81 views

Manipulating formal vectors

I want to work with a formal vector space spanned by integer triplets: $$ V=\text{span}\{(a,b,c):a,b,c\in\mathbb N^3\}, $$ such that Mathematica can do additions for me. For example,if I input ...
1
vote
2answers
134 views

How can I select elements that are true

I have a list of lists. For example, list = {{0,1,0,1,true},{0,0,0,0,false},{0,1,1,1,true},{1,1,1,1,false},{2,2,2,2,false}} I'd like to find all lists that ...
0
votes
2answers
196 views

Apply Eigenvalues to a list of matrices

I would like to apply Eigenvalues[] to a list of matrices as in the following ...
19
votes
3answers
901 views

How to extract the edge from a set of points

I have an accumulation of points representing a body as you can see in the image below. From this data I want to generate a list of points or a curve, which is the envelope. The first idea was a ...
2
votes
2answers
130 views

adding vectors of unequal length [duplicate]

If I have hundreds of vectors of unequal length that I need to sum, what is the cleanest way to do so? So, if I have as input inp={{a,b,c,d},{e,f,g},{h}} I want ...
11
votes
3answers
519 views

How to add lists with unequal length?

Given lists of unequal lengths, I want to add them together element-wise, treating missing elements as zero. For example, {1, 2, 3} + {a, b} + {x} should give ...
-2
votes
2answers
428 views

How do we solve third order nonlinear differential equation f’’’+ff’-f’2-Re2 f’=0

How do we solve third order nonlinear differential equation f’’’+ff’-f’2-Re2 f’=0 f(0)=0,f'(0)=1,f(Infinity)=0 From the OP's comment: ...
17
votes
2answers
2k views

How to fit 3 data sets to a model of 4 differential equations?

I'm a biologist and a newbie in Mathematica. I want to fit three data sets to a model consisting of four differential equations and 10 parameters. I want to find the parameters best fitting to my ...
0
votes
1answer
106 views

Plotting error table in 3D

I have an error table which includes three parameters(error, epsilon and step size) and the matrix is not square. Now, I want to plot my data in 3D, but didn't manage to do it. My table is as follows ...
10
votes
2answers
525 views

How to create custom Graphics primitive?

How to create custom Graphics primitive? It should have the following properties, resembling properties of built-in geometric figures, like ...
2
votes
0answers
54 views

Equation involving hypergeometric functions

I want to solve this equation but nor NSolve nor Solve are able to do this. ...
0
votes
0answers
46 views

How to obtain all minima? [duplicate]

If you Solve an equation, you obtain all solutions. But If you NMinimize a function, you only get one minimum. The question ...
1
vote
0answers
51 views

Panel size undesired behaviour

This is next question from the series: better avoid Panel if you care about details. previous about FrameMargins In the ...
7
votes
1answer
367 views

Exporting EPS figures with dashing from ListPlot

I am having difficulties exporting EPS figures. If I use the LineLegend option to create a dashed or a dot-dashed line, it seems ok in Mathematica 9.0 e.g.: But the problem came out when the ...
0
votes
0answers
22 views

Subscripts and Simple Forumlas giving unexpected answer [duplicate]

I trying to do a tensor problem but for simplification I'll only ask for assistance with one simple part. I set my variables using subscripts like so.. $Subscript[y, 1] = - .23556;$ But when I try ...
4
votes
1answer
147 views

How to differentiate between formatted and unformatted strings?

StringQ returns True both for unformatted and internally formatted strings. To get True only for unformatted ones I have thought up the following function stringQ. Please, can you point out ...
2
votes
2answers
324 views

Drawing tubes with a While loop

I'm trying to make a plot with many objects in it using a While loop. Something like the following: ...
2
votes
1answer
1k views

Solving Heat equation [closed]

I want to compute the exact solution of the heat equation but I got an error. u(x,t) (equation of transmition of heat) is the solution of this differential equation: $$du/dt - \alpha d^2u/dx^2 = 0$$ ...
3
votes
2answers
188 views

Finding similar expressions in list

I have a function that returns to me lists of expressions, like: ...
8
votes
1answer
378 views

How to import a large (~50Mb) json file in mathematica

I am trying to import a 46Mb json file into mathematica (which by the way I exported using mathematica) but its failing with the following messages: ...
13
votes
4answers
561 views

Is it Possible to change dashes into circles with Plot command?

Is it possible to change the Dashed Style of a curve into circles with Plot command ? ...
3
votes
0answers
72 views

LibraryLink parallel performance

I'm trying to use a LibraryLink function in parallel. It is an embarrassingly parallel problem, so that no dependency between those parallel tasks. However I can only get the parallel efficiency about ...
0
votes
1answer
144 views

Making an animation which displays a rotating object [closed]

I want to rotate the geometry obtained whith the input: movil = ExampleData[{"Geometry3D", "SpaceShuttle"}] But it shows an error message : Graphics is not a ...
1
vote
3answers
136 views

Area enclosed by two functions

i want to calculate the area percentage of a function in a certain regime above a constant threshold. For example: f[x] = sin[x] x² from 0 to 2 with a threshold ...
4
votes
1answer
197 views

Permanently set options such as metric units for W|A queries

Mathematica lets me be so lazy that I don't even have to switch to a browser to check the weather report: The only problem is that it will automatically display the temperature and wind speed in ...
0
votes
2answers
89 views

ToExpression an array

I have a .dat file. I would like to convert a big array of strings(that's what I havein the .dat file) into an array of numbers, for example ...
1
vote
1answer
287 views

Prevent FullSimplify from converting trigonometric expressions to exponential

There's an option for FullSimplify, which is Trig, and with it I could prevent a trigonometric identities from being used. I'm ...
1
vote
2answers
191 views

Mathematica can't minimize a function

Mathematica seems not to be able to minimize this univariate function over integer arguments, $r>2, r \in \mathbb{Z}$. ...
1
vote
0answers
73 views

Controlling output of graphics, the role of “;” and code structure/formatting

";" is described under Compound Expression as a delimiter, such that only the output of the last item in the compund expression is given. Situation: 1/ Print[] produces output whether followed by ...
2
votes
1answer
169 views

Importing web page data

I tried importing a webpage using Import: ...

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