0
votes
1answer
170 views

Eigen energies of 2D time independent Schrödinger equation

Firstly, I am aware that a similar question of this type was asked, but it was not helpful as it was only one dimensional (so please don't mark my question as a duplicate) The trouble I am having is ...
9
votes
1answer
440 views

Geocentric, Earth-fixed, coordinates of Sun, Moon (and others objects eventually)

I know I can get "HelioCoordinates" of the Earth and the Moon with ...
0
votes
0answers
51 views

DisplayFormula badly rendered if style is set before writing

If I have to write a display formula, I go to the cell after the text cell I'm currently into, select the DisplayFormula from the Style menu and then write. The ...
2
votes
1answer
66 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
1answer
74 views

Unnecessary free space under the figure

Here is the data ...
1
vote
1answer
54 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
114 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
147 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 ...
3
votes
2answers
258 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
433 views

All integer should be equal

I have a list of 10 integers: ...
1
vote
2answers
83 views

Create a random 2×2 matrix with a repeated eigenvalue and single eigenvector

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 ...
11
votes
1answer
306 views

Empty Blank regression in v10.1

Bug introduced in 10.1 and fixed in 10.2.0 In v10.1.0.0 on Linux, when Blank[] is used in Alternatives with pattern that can ...
2
votes
0answers
41 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. ...
2
votes
1answer
121 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
228 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
219 views

How to check if all the members of list lies in specific range

I have a list the form: ...
2
votes
0answers
89 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
33 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.!!!!!!!!
2
votes
2answers
209 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 ...
1
vote
3answers
258 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
51 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
166 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
98 views

How to set DisplayFormulaNumbered Font style to Times New Roman? [duplicate]

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 ...
5
votes
1answer
103 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 ...
1
vote
1answer
50 views

Consistency between MousePosition and WindowMargins

MousePosition["ScreenAbsolute"] absolute position within the complete screen display WindowMargins specifies the ...
2
votes
1answer
89 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
44 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 ...
8
votes
2answers
194 views

SetOptions for CoordinatesToolOptions for DateListPlot?

Bug introduced in 10.0 and persisting through 10.2.0 or later DateListPlot does not respect my Options setting for ...
4
votes
1answer
178 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
52 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
72 views

NDSolveValue with Map

I have: ...
9
votes
1answer
115 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
103 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 ...
3
votes
1answer
106 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 ...
2
votes
1answer
97 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
220 views

Translating Histogram

SeedRandom[1]; RandomVariate[NormalDistribution[], 100]; Histogram[%, Automatic, "Probability"] The above code produces a histogram like I want to translate ...
2
votes
1answer
57 views

Change ColorScheme of DistributionChart

The "ColorScheme"of a DistributionChart can be changed using the ChartElementFunction like in the following example: ...
4
votes
1answer
123 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. ...
5
votes
1answer
214 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
93 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 ...
5
votes
6answers
335 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 ...
4
votes
0answers
50 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
75 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
72 views

Simplify on a structured array

Why doesn't Simplify and FullSimplify operate on object generated using SymmetrizedArray? ...
10
votes
1answer
176 views

Enigmatic message about MaxBend

Referring to the method I proposed for Problem with ParametricPlot Mathematica 10.0.2 throws an enigmatic error message: ...
4
votes
1answer
255 views

NDSolve to solve a PDF

I would like to solve numerically the following PDE: $$ \frac{\partial}{\partial t} p(x,t)=-\frac{\partial}{\partial x}p(x,t)+\frac{1}{2}\frac{\partial^2}{\partial x^2}[x^2\,p(x,t)],\;x\ge0,\;t\ge0, ...
0
votes
0answers
60 views

Integro differential eq boundary difficulties

I'm trying numericaly solve simple integro-differential equation, but have some problems with boundary conditions. System: ...
2
votes
0answers
44 views

Calculating number of discernible colors in CIE La*b* space

How can Lab space be easily splitted into unity cubes and determined number of cubes that colours of certain image occupy?
3
votes
2answers
80 views

Is there a function for “flattening out” and setting to 0 an expression?

For example if I have some complicated expression (all variables are positive integers) but I want to multiply everything out so there are no denominators and then rearrange so that it is equal to 0, ...
4
votes
4answers
152 views

Express block matrix in terms of matrix basis

I'm trying to construct a function that returns the multiplication table of a matrix Lie algebra. Assuming a basis of matrices, my definitions: ...

15 30 50 per page