# All Questions

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 ...
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 ...
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 ...
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 ...
74 views

### Unnecessary free space under the figure

Here is the data ...
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. ...
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 ...
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 ...
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 ...
433 views

### All integer should be equal

I have a list of 10 integers: ...
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 ...
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 ...
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. ...
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: ...
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 ...
219 views

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

I have a list the form: ...
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 ...
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.!!!!!!!!
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 ...
258 views

60 views

### Integro differential eq boundary difficulties

I'm trying numericaly solve simple integro-differential equation, but have some problems with boundary conditions. System: ...
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?