# All Questions

0answers
46 views

### Creating Vector Field Plots for an Implicit Equation [on hold]

I am having difficulty creating a vector field plot for the implicit equation Log[(2x-1)/(x-1)] == t (* Did your best to use Mathematica syntax *) Where ...
1answer
142 views

### Why is Random faster than RandomReal?

As of version 6, Random[] was superseded by RandomReal[ ] etc, but both still work perfectly well. Playing with some timing ...
1answer
77 views

### How to make image3d smaller? Is ImageResolution useful?

I want to make the output of Image3D much smaller. For example ...
2answers
189 views

### How do I plot a space curve as a ribbon?

I know Mathematica has a built in Tube function, but I want to be able to change the parameters of a ribbon and visualize that. Is this possible? How do I do this? ...
1answer
116 views

### I want to compute the derivative of Black and Scholes option

Good evening to everybody, my question is about computing the derivative of a Black and Scholes option and to draw it. My code is ...
0answers
28 views

### MatrixForm in Mathematica [duplicate]

I wanted to do subtractions between to matrices and I did the following ...
1answer
56 views

### how to generate a 3d graph of HCP crystal structure [duplicate]

I am confused with lattice parameter and the basis. The structure I generated is not HCP. To verify this, one could use this plotting function from the answer to Can a LatticeData image be displayed ...
0answers
27 views

### how to plot many curves for different values of a certain parameter [closed]

how to plot many curves for different values of a certain parameter of a function? how to plot many curves for different values of a certain parameter of a function? i.e. i need to get one figure ...
2answers
68 views

### How to define a complicated function inside the body of Compile?

I want to compile a function in a way to keep its memory footprint down. In the example below, I am trying to compile a function f that makes three calls to ...
1answer
64 views

### How to get the analytical solution of this equation set

There is a equation set: {2 x^2 + 49 - 7 x - 2 x Sqrt[x^2 + 49 - 7 x] Cos[rad] == (7 - x)^2, 2 x^2 + 49 - 7 x - 2 x Sqrt[x^2 + 49 - 7 x] Cos[rad + Pi/3] == 49} ...
2answers
55 views

### Manipulate slider freeze, and empty value in box

Here's a MWE code to show two problems I'm experiencing with the sliders and their value box, under Manipulate : ...
1answer
46 views

### How to make an empty list inside a module program? It consatly spews errors [duplicate]

Okay, so, I'm trying to write a program within the module. It goes like this: create empty list, join it with a sample from a certain set called MyList, and then repeat it certain number of times. ...
1answer
54 views

### NumberForm pesky warning from Manipulate

I'm using the NumberForm command inside a Manipulate environment, and in some special cases Mathematica gives a pesky and mostly useless warning message : NumberForm::sigz: In addition to the ...
0answers
31 views

### weird behaviour of Listable fortran Librarylink function: different result each evaluation

I am working with fotran librarylink function currently. In this post, I will show some weird result of Listable fortran librarylink generated by intel compiler under windows (I tried gcc on linux the ...
1answer
69 views

### Is there a bug of InverseDistanceTransform?

This is a example of documentation about InverseDistanceTransform. But this is my picture But it doesn't work: ...
5answers
439 views

### Partitioning a list when the cumulative sum exceeds 1

I have a long list of say 1 million Uniform(0,1) random numbers, such as: dat = {0.71, 0.685, 0.16, 0.82, 0.73, 0.44, 0.89, 0.02, 0.47, 0.65} I want to ...
1answer
63 views

### what do those signs #1, #1^2, #1^3, & mean here? [duplicate]

I have read common pitfalls page and the documentation page but I still don't understand what do those signs mean here? ...
0answers
20 views

### Private Style in a StyleSheet with preformatted text

I want to create a new Style in my private StyleSheet. I duplicated the Style "Text" and made some alterations. Now I want that a Cell with this style has an expression already filled in, for example ...
1answer
75 views

### Why a part of this expression, similar to another, is left unchanged?

An expression has one of its part replaceable and one, strictly similar, that isn't. Please, can you point at the difference ? I can't pinpoint the complication ... The FullForm of ...
1answer
54 views

### NIntegrate::inumri: error [closed]

I am getting the following error: NIntegrate::inumri: The integrand c (1-0.6 (1-(1+Times[<<2>>])^0.5)-0.4 (1- (1+Times[<<2>>])^0.5)) (1-0.6 (1-(1+Times[<<2>>])^0.5)-0.4 (1- ...
0answers
35 views

### WhenEvent and Resetting of Variable in PDE when operation succeeds

I have had success in using WhenEvent to reset or change a variable within NDSolve with ordinary differential equations. My ...
0answers
52 views

### Fourier-style solutions to differential equations, not piecewise polynomials

NDSolve returns piecewise polynomials. Is there any way I can get a single (non piecewise) function consisting of sines and cosines instead? Sort of a "Fourier approximation" to the solution of my ...
2answers
167 views

### Plot of $sin(x^x)$ is missing from $x=143$

When plotting the graph of $sin(x^x)$ I noticed that there is no plot from about $x=143$. I don't suppose there is a purely mathematical explanation for this? So, why is there no graph in ...
0answers
75 views

### Phase space of a system of differential equation

I have a system of three Coupled nonlinear equation of a physical system and i would like to plot the phase space. My system is a chaotic system dependant of three variable dependant of time (l1, ...
1answer
67 views

### Problems with QueueingNetworkProcess [closed]

I have a two stage queueing network and want to vary the number of servers at the second node. The input data and the Manipulate command is below: ...
0answers
69 views

### Possible memory leak in FindMinimum? (MMA v10.0)

So I was running some code when I noticed Mathematica was gulping memory, and after some debugging I think the culprit is found. It turned out the function ...
2answers
152 views

### Symbolic vs numerical integration

This is related to a question that I asked before but didn't resolve quite well. I want to obtain the solution of the following expression analytically: ...
0answers
32 views

### File filter in SystemDialogInput

I want to write a SystemDialogInput function that allows user to choose a file from a directory. In the directory, there are two kinds of image files: Atom images: The name of the file is in the ...
2answers
84 views

### MeshRefinementFunction missing points

I'm doing some FEM on a rectangular region with a spherical cavity: ...
1answer
57 views

### How to refer a number in a list with two columns, first one is a number and the second one is empty? [on hold]

Let's say, I have defined a list as list = {{-31, -31}, {52, }, {34, -11}, {-38, }, {78, -44}, {-36,14}, {-9, 98}, {33, 6}, {82, 99}, {-85, -10}} As you can see, ...
5answers
347 views

### How to extract a contour line (or a region) from a ContourPlot?

Given a ContourPlot with a set of contours, say, this: is it possible to get the contours separating domains with the different colors in the form of lists? ...
0answers
31 views

### Changing from Cartesian to polar coordinates in partial differential equation [duplicate]

I have a partial differential equation: $$\left(x^2+y^2\right)\frac{{{\partial ^2}u(x,y)}}{{\partial {x^2}}} + x^2\frac{{{\partial ^2}u(x,y)}}{{\partial {y^2}}}=0$$ How to change from Cartesian to ...
1answer
116 views

### Add terms to nested list

Suppose I have a nested list of the following: list={{1,2},{5,8},{4,1}...} I would like to add a number to each first term of the list. The output would be ...
1answer
89 views

### Automatic text-wrapping in labels in TimelinePlot

Part-related to this question and part-related to this one, I would like to make use of the new features of TimelinePlot in 10.3, but would like to incorporate some ...
1answer
27 views

### Length in Compile encounter “type Integer encountered in assignment of Type Real ”

Compile[{}, Module[{n}, n = Length[{1, 2, 3, 4}]; n = n/2]] The above code will emit errors Compile::cset: Variable n of type _Integer encountered in ...
1answer
56 views

### ParallelTable should distribute dedicated evaluation range to different kernels

I have 4 kernels and would like that in ParallelTable: ...
0answers
40 views

### Optimization (minimization) of equations with conditions [closed]

I need to minimize the expression a+(b/3) + c under the conditions: ...
2answers
60 views

### How to solve for the eigenvalue in matrix? [closed]

For which value of $a$ in the matrix {{a,2}, {3,4}} has the matrix eigenvalue of $0$? How to solve it in Mathematica?
4answers
196 views

### How to generate two group of $n$ random numbers in $U(0,1)$ such that sum of these two groups equal? [closed]

I want to have two groups of $n$ random numbers $u_i$ and $v_i$ in $U(0,1)$, such that $\sum u_i = \sum v_i$ What I tried is: I can firstly get $u_i$ by ...
1answer
24 views

### Why can't I change the Magnification in Printout Style in Default.nb

This happens with Mathermatica 10.3.1.0: When working with a notebook, I can choose between different working environments. However, they inherit their settings from Default.nb situated at ...
0answers
45 views

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2answers
96 views

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2answers
95 views

### I want to plot a list of points with specified t and x[t] coordinates [closed]

I have this code: ...
2answers
68 views

### intermediate steps of simplification of algebraic expression without evaluation [closed]

I am using MMA do do some algebra and I need to do some simplification. For example, I have the following expression  x^2 \left( \frac{6 \left(2 c_1 x^6+c_2\right)}{x^4} \right)-x \left( 4 c_1 ...
1answer
45 views

### How to represent one variable in terms of others in a system of equations? [closed]

I have an pretty complex equation set But when I clicked Ctrl+Enter (a.k.a Evaluate Cell), nothing happened. What should I do?
0answers
29 views

### How define shortcuts to specific OptionInspector points?

I often assign label to cells by OptionInspector (SHIFT + CRTL + O) > CellFrame > etc. It would be great to have the possibility to jump directly to CellFrameLabel or, even better, to edit the label ...
0answers
29 views

### How to draw database diagram when connected to SQL Server via Mathematica [closed]

Is there a way to draw database diagram in mathematica?
0answers
88 views

### What is recommended way to define my function option

In Mathematica 5.x days many packages used the following standard mechanism to read option values ...
0answers
35 views

### Generation of Space Representation of non-crystallographic Point Groups

In Mathematica the command FiniteGroupData[{"CrystallographicPointGroup",<group number>}, "SpaceRepresentation"] yields the space representation ...
2answers
52 views

### Manually assigning Axes label position in Plot3D

How can I adjust the position of axes labels with respect to the axes they are bound? Like shifting slightly right or left. I do not what to destroy the graphics' dynamics and render it 2D. ...

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