2
votes
1answer
48 views

Can association be used to find the maximum key less than a specific number?

Suppose we have an association assoc. assoc = <| 1 -> 1, 3 -> 2, 5 -> 3, 7 -> 4, 20 -> 5|>; Instead of ...
0
votes
0answers
23 views

Generating a list consisting of function values like in a triangular matrix

A goal is to generate a SymmetrizedArray of dimension n^k with specified symmetry (let it to be ...
0
votes
1answer
71 views

Unnecessary free space under the figure

Here is the data ...
1
vote
1answer
38 views

ListLogLinearPlot with Legends

I need to plot this data in Log scale for both axes, and also need to add a legend. But since they are joined dots, the legend that appears is just a dot instead the plotstyle I choose. ...
0
votes
1answer
58 views

Series with a specified number of terms

I'm doing calculations with Series where I don't know the power of the leading order term. I would like to keep a specified number of terms, but since I don't know the leading order this is proving ...
1
vote
2answers
114 views

Plotting points on the horizontal line

I have list such as list = {1, 5, 2, 6, 3,...} and I need to plot the numbers from the list on a horizontal line such that there will be on a place on horizontal ...
1
vote
1answer
71 views

NonlinearModelFit: fit a vector-valued function to a data vector

I have a vector of data points: data = 10 Sin[#/10] + RandomVariate@NormalDistribution[] & /@ Range[200]; And I have model that provides the complete ...
4
votes
6answers
359 views

All integer should be equal

I have a list of 10 integers: ...
0
votes
0answers
83 views

Using Runge-Kutta method to find arc length [duplicate]

I don't know much about using the Runge-Kutta method in Mathematica, so I have to ask a straightforward question: How can I use Runge-Kutta to numerically approximate the parameter t of this curve in ...
0
votes
2answers
36 views

Create a random 2x2 matrix with a repeated eigenvalue and single eigenvecor

Does anyone have a good technique for creating a random $2\times 2$ matrix that has one eigenvalue of multiplicity two, but only a single eigenvector? And more generally, has anyone written a ...
5
votes
0answers
151 views

Empty Blank regression in v10.1

In v10.1.0.0 on Linux, when Blank[] is used in Alternatives with pattern that can match a sequence, whole pattern unexpectedly ...
2
votes
0answers
26 views

Export PDF margins different in V9 & V10 compared with version 7

PDFs in version 9 and 10 have bigger margins than in version 7. I can't find any differences in the settings. I'm using A4 paper and it looks like version 9 might be trying to use letter size. ...
0
votes
0answers
21 views

Controlling scaling of multiple vector fields in VectorPlot3D

I'm trying to plot the electric and magnetic fields of a relativistically moving electric charge using VectorPlot3D, and apply "Manipulate" to change the velocity. The code I'm using is as follows: ...
0
votes
1answer
105 views

Time evolution of a wave packet from the time-independent Schroedinger equation [duplicate]

Starting off with the time-independent Schroedinger equation (TISE) $\quad \quad -\frac{\hbar^2}{2m} \nabla^2 \psi + V(r, \theta) \psi = E\, \psi,$ I would like to study the time evolution of an ...
1
vote
4answers
161 views
2
votes
0answers
56 views

Does anyone have a debugger that works in version 10.+?

The debugger from mma version 10.0 to 10.1.0 is broken for me. I have Windows 8.1 64-bit. When I step through a function using the debugger then the function is run several times. This problem didn't ...
0
votes
0answers
30 views

Problems with my units? [duplicate]

I have my own unit is called "Euros" Input:5 Euros -3 Euros Output:2 Euros Input:5 Euros - 5 Euros Output:0 How can I make to get 0 Euros? Output: 0 Euros->That I want to get.!!!!!!!!
0
votes
0answers
22 views

Problem of HTMLFragment, strange output

In the help page of HTMLFragment ...
2
votes
2answers
158 views

Are there any good mass row/column swapping functions for matrices?

I have the following matrix Keeping the 20 row and 20 column fixed (so the 21st rows and columns because I started at 0)...how do I push each row and column back one spot? I need to push the 0th row ...
0
votes
0answers
36 views

Is it possible to import Matlab “.fig” files in Mathematica?

Is it possible to import a ".fig" file made in Matlab into Mathematica? If I try the usual Import[filename] it produces an error ...
-2
votes
0answers
42 views

A map from line to unit circle [closed]

A map from line to unit circle. Which is define as: f(x)= e^2πix Please explain it, which element of line is going to map at which element of circle ?
1
vote
3answers
201 views

Writing code to update a large matrix?

How can I write a code to update a matrix based on certain rules? I plan on constructing a large matrix, and I cannot submit entries one by one. The rules for the matrix are as followed: $$ ...
0
votes
2answers
37 views

Expand “hierarchical” system of equations

I have a system for equations that is structured hierarchically: - Level 0: these are base variables that I can measure from a process (e.g. a,b,c) - Level 1: these are variables derived from Level 0 ...
1
vote
1answer
109 views

Approaches to solving non-linear systems of equation with assumptions

The specific type of system looks as follows: \begin{align} (r-r')x+4d_1 x^3+4d_{12}xy^2 &= 0 \\ (r+r')y+4d_2 y^3+4d_{12}yx^2 &= 0 \\ \end{align} Where $r,r',d_1, d_2, d_{12}$ are all real ...
0
votes
0answers
21 views

How to set DisplayFormulaNumbered Font style to Times New Roman?

I'm writing a lecture notes with lots of formula in notebook which will be saved as pdf later. In my notes many DisplayFormulaNumbered cells were used, where the default FontStyle were Arial, which ...
3
votes
1answer
74 views

Is Sow/Reap compatible with Composition?

I'm trying to figure out why these two pieces of code return different results. As expected, f[Reap[Sow[x]]] gives ...
0
votes
1answer
22 views

Consistency between MousePosition and WindowMargins

MousePosition["ScreenAbsolute"] absolute position within the complete screen display WindowMargins specifies the ...
2
votes
1answer
71 views

an Integral that should be doable:

Integrate[Cos[\[Beta]] Exp[I z Cos[\[Beta] - \[Alpha]]], {\[Beta], 0, 2 \[Pi]},Assumptions -> z \[Element] Reals] correct answer is [ I think ]: ...
0
votes
1answer
35 views

How to have default case in Which? [closed]

Saying we have a function: a[x_] := Which[x === 1, "AAA", x === 2, "BBB", _, $Failed] How can I make this function to be equal to ...
4
votes
2answers
89 views

SetOptions for CoordinatesToolOptions for DateListPlot?

DateListPlot does not respect my Options setting for CoordinatesToolOptions: ...
4
votes
1answer
97 views

Converting a sum into $\Sigma$ notation

I have a simple expression of the form $\quad \quad t^5+t^4+t^3+t^2+t+1$ and I want Mathematica to convert this to the form $\quad \quad \sum _{i=0}^5 t^i$ Is there a way to do this?
0
votes
2answers
47 views

How can I match some parts of an expression?

Suppose I have an expression like Abs[x+I y]+Sin[Abs [c+ I (d+e)]], and I want to replace all expressions in the form of ...
0
votes
1answer
43 views

NDSolveValue with Map

I have: ...
8
votes
1answer
85 views

How to synchronize the display of dynamic objects?

I was looking at this question, which asks to keep the orientation of some 3D graphics objects constant (relative to the viewer) while rotating the rest with the mouse. I thought that maybe the ...
3
votes
1answer
54 views

SystemModeler join wires

I'm using SystemModeler and I'm trying to understand what is the equivalent for Simulink's Ctrl+drag to create a wire coming out of an existing wire. I am trying to make a wire come out of an existing ...
1
vote
1answer
64 views

Why is the Spherical Bessel Function acting strangely at this point?

I'm doing some computation that requires the use of Spherical Bessel Functions of the 1st kind, at high orders and values. So, I managed to find this, while running it over a wide range of values. I ...
-1
votes
0answers
40 views

How can I define a function to make symbols? [duplicate]

I want to define a function that makes symbols like this: L[1] A1 L[2] ...
1
vote
1answer
43 views

How to draw scatter plot with errorbars from huge lists of data in a fast way?

I want to make a scatter plot using two huge lists that give the $x$ and $y$ coordinates of the points. To each $(x,y)$ point I want to add a symmetric errorbar (I have anothe list with the errors) in ...
4
votes
3answers
156 views

Translating Histogram

SeedRandom[1]; RandomVariate[NormalDistribution[], 100]; Histogram[%, Automatic, "Probability"] The above code produces a histogram like I want to translate ...
0
votes
0answers
46 views

No solution for a system of equations

I am a newbie in Mathematica and I face a problem in my attempt to solve a system of equations. The system is the following: ...
2
votes
1answer
39 views

Change ColorScheme of DistributionChart

The "ColorScheme"of a DistributionChart can be changed using the ChartElementFunction like in the following example: ...
4
votes
1answer
84 views

Constant orientation of graphics in Graphics3D

I have been facing a challenge for programming for quite a while now, and I think it is now time for me to consult some Mathematica experts: I would like to draw a three-dimensional graphic, e.g. ...
4
votes
1answer
87 views

Checking if a symbolic matrix is positive semi-definite

As far as I can tell, there is no way to tell the builtin PositiveSemidefiniteQ about assumptions on symbols. For example, the matrix ...
0
votes
1answer
66 views

Plotting Riemann surface of $\sqrt{z}$ in rectangular coordinates

I'm trying to plot the Riemann surface of $\sqrt{z}$ with this command: ParametricPlot3D[{t,u,Re[Sqrt[t + I u]]}, {t,-1,1}, {u,-1,1}]; but the output isn't ...
0
votes
1answer
47 views
4
votes
6answers
215 views

Indexed Map Thread

I'm attempting to MapThread a function of two lists that requires the index of the list values. For example, MapThread[#1*i+#2*j&,{{a,b,c},{e,f,g}}] Where #1 ...
0
votes
1answer
72 views

Plotting a NDSolve solution

I'm working on a neutrino oscillations problem, and am running into issues ploting the solution to my differential equations. The equations have non-analytic solutions so I'm using the ...
4
votes
0answers
41 views

Wrong autogenerated package from notebook containing #key and Part as subscript

Bug introduced in 10.0.0 and persisting through 10.1.0 or later Mathematica v10.1.0, under Windows 8.1 x64 Mathematica v10.0.2, under Windows 1) Define a function in an initialization cell: ...
0
votes
1answer
40 views

Is there a function or option to collect factors under one radical sign?

One of the things that frustrates me most about Mathematica's symbolic manipulations is the fact that output is often presented quite differently than most humans would write it. This is especially ...
2
votes
1answer
52 views

Simplify on a structured array

Why doesn't Simplify and FullSimplify operate on object generated using SymmetrizedArray? ...

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