# All Questions

72 views

### How to specify the number of precision digits for columns using DatabaseLink functions and options

Some databases (e.g. MySQL) does not store decimal places for seconds unless the number of digits needed is directly specified (e.g. DATETIME(4) for 4 digits) when creating the table in the database. ...
57 views

### Designing a loop that fetches 5 random vectors each with 5 components from a set of 10 until Linear dependence is found

I am currently trying to find a way to make a loop that will select 5 random columns without replacement of a 5x10 matrix until it finds a determinant equal to 0 out of the new matrix formed by the 5 ...
71 views

### LevelScheme Ticks hidden behind DensityPlot or SmoothDensityHistogram

I'm having a problem where the LevelScheme ticks are hidden by my SmoothDensityHistogram. In the above figure, I am sure that the ticks are there since you can ...
104 views

I have: ...
38 views

### How to solve a system of equations which includes vectors? [duplicate]

I'm starting to wonder if this is something that mathematica just can't do? I thought something like this might work: ...
336 views

### Mimic a procedural, recursive clustering algorithm for site percolation using functional programming

Sorry in advance for my logorrhea: I just want to make sure all of the information is here. Context and Question I am investigating site percolation on a square lattice. I have a working, depth-...
330 views

### Solving a two variable two equation trig expression

I am trying to use Solve to get what two angles (A and B) are in a problem I have. ...
169 views

### Threading elements over corresponding elements in the second list

I often need to merge two lists like the following: $A=\{\{0.1\},\{0.2\},\ldots,\{1\}\}$ $B=\{\{x_1\},\{x_{21},x_{22},x_{23}\},\{x_{31},x_{32},x_{33}\},\ldots,x_N\}$ in a way to ideally obtain a ...
64 views

### Reducing a system of vector equations

I'm trying to solve a system of vector equations. I know this is solvable since I've done it myself by hand (I reduced it to solving the root of a quartic anyway). I'm trying to do it in Mathematica ...
256 views

### Logarithmic x-axis for ListPlot?

I have a list of points that I am trying to plot. Is there a way to make a ListPlot where the y-axis increases normally by 1 every interval but the x-axis ...
69 views

### Mathematica Code Involving For Loops Not Completing All Iterations [closed]

First of all, thank you for taking the time to read this. I'm working on a portion of code related to the genetic algorithm that is not producing the expected results. What the code is supposed to do ...
426 views

### Why Mathematica cannot apply The Fundamental Theorem of Calculus automatically?

For some reason Mathematica cannot evaluate this definite integral: ...
267 views

### Applying function to cartesian product of two lists

I have two lists X = {1, 2, 3}; Y = {5, 6, 7, 8}; I want to apply function g[x,y_,z_] to all pairs from X*Y, so I need to ...
67 views

### Change input parameter order in a function

I'm a beginner in Mathematica programming and I'm trying to understand how input parameters work in Mathematica's function. I encountered a problem with the sequence/order of the input parameters of ...
21 views

### Is there a list of function shorthand notations, shortcuts, and other various symbols somewhere? [duplicate]

For example how you can use // to apply some functions like Simplify instead of enclosing the argument in square brackets. Or ...
41 views

### What does __Rule do in Mathematica? [closed]

What does __Rule do in mathematica? I understand the __ is used for any repeated expression, but why is the Rule appended at the end? For example: Import nested JSON file Thanks!
339 views

### Contour lines over SmoothDensityHistogram

I am using SmoothDensityHistogram on a data set of the form {{x1, y1}, {x2, y2}, …, {x_n, y_n}}, and I would like to also show ...
114 views

### Change cell frame color in stylesheet

I am trying to make a custom stylesheet, but I am not able to get rid of the cell frame color from the base stylesheet. In particular, I have: I have changed the background color of the cell to ...
94 views

### Writing Assistant is always on top

Title explains it. Even when I am asking this question on google chrome, Writing assistant is still on the screen.
123 views

### Stability analysis of transcendental equation (stability crossing curves)

I am working with a non-linear delay system with three scalar delays. After taking the Laplace transform of the linearized system, the characteristic function is a transcendental equation with three ...
1k views

### What do the X and Y axis stand for in the Fourier transform domain?

In Wolfram Mathematica the function Fourier has the following declaration Fourier[list] And after a list is given to the ...
245 views

### How to make Mathematica use system GTK style under Linux?

Under Linux, Mathematica uses preinstalled QT themes, but I'm sure that it's possible to make it use system GTK style. How?
180 views

### ParallelTable slower than Table in the presence of an Association?

So after testing some things I am completely reformulating my problem. First an example ...
147 views

### Calculate area between two multivalued curves

I have to calculate the area between two curves which will give me the result of a particular quantity. However, both the curves are multivalued functions. Here is a data set showing the region where ...
544 views

### Solving an equation takes too long

I am trying to solve the following equation func[a, b, c, d, e] == 0 where ...
119 views

### Match groups in regular expressions

I'm trying to understand Mathematica's pattern matching in strings, but I have some doubts. 99% of the time I need to a) check if a match occurs and b) retrieve the matched patterns. I come from ...
181 views

### Calculate the standard deviation between two sets of data points

I have two sets of data points, ...
276 views

### Fitting a Parametric Curve

I apologize if this question is obvious or simple. I'm in high school and have started playing around with Mathematica only recently. For my Calculus Final, I am supposed to use rotation about the $y$...
178 views

### Implementing AnglePath in Mathematica 10.0

Does anyone have an implementation for AnglePath (see AnglePath Documentation and example usage) in Mathematica 10.0?
108 views

### Is it possible to find the size of a variable in a notebook?

I have a fairly large a list of matrices matsLst, which takes about 15 minutes to compute (but computes successfully each time). I can test in the notebook that ...
70 views

I am trying to implement the FFT algorithm when $n=3^k$, but maybe my code is wrong. Are there any suggestions for improving my code? ...
246 views

### Create a table of Mean Values and Standard Deviations from data list

I need to create a table of the Mean Values and Standard Deviations of 18 columns of data from a table. I know how to compute the Mean and Standard Deviation for the different columns, but am unsure ...
159 views

### Lookup with default broken in Dataset

Given an Association, ...
54 views

### Problem with plotting a piecewise function [duplicate]

I'm having a very puzzling issue with piecewise defined but smoothly continuous functions. I have a perfectly continuous piecewise function defined as ...
69 views

### ListlogLogPlot can't work on y axis

I have a table: ...
100 views

### Compiling a summation

I have a sum over Legendre polynomials which I'm trying to speed up. I've come across the suggestion of using Compile to speed up code in previous answers around ...
123 views

### Meaning of Pattern at derivatives of arbitrary functions

I want to derivate some general functions like D[F[x[r_, p_], y[r_, p_]], r] or this simpler one D[F[G[x_]], x] . When I ...
97 views

### How to find µ (Gravitational constant mass product) with PlanetData?

I would like to use PlanetData to get µ, the product of the Gravitational constant G and a ...
157 views

### Finding the discrete Fourier transform for a simple oscillator?

Here's what I want to do, initially at least: I have an oscillator, it's in some force field, I've integrated it using the Euler method, so I have a list of points of the form {t,x}, where t is the ...
87 views

### Using Manipulate to determine intersection of two surfaces

Here is what I have done thus far: ...
60 views

### How can “lift” a plot which passes near y=0? [closed]

I know this plot below does not touch b=0. How can I lift it in order to see those values near b[M]=0? I tried ...
51 views

### Grouping by multiple coefficients

Good day! I have an output equation that has a very large amount of coeff. b(x,y), like so: ...
146 views

### Plot: Construct an Amoeba

I am trying to plot an Amoeba, e.g we consider the polynomial f(z, w) = 2 z - w + 1 and solve it explicitly , the solutions satisfy the equation ...
182 views

### Needs cannot open a package

I have a package and notebook in the same directory, but Needs is throwing an error "Cannot open EField.m". I have tried several variations of this. I am ...
59 views

### Display a part of a notebook when MMA has done evaluating it

When you evaluate a notebook, it begins to slide upward and shows you a different part of your code, several cells upstream of the notebook... I was wondering if there is a command that could always ...
179 views

### Defining a 2-variable function over voronoi diagram

I am new to Mathematica & I am facing a problem as follows: I have created a Voronoi diagram and now I want to assign to each region, a value, i.e., I want to extend this Voronoi diagram to form a ...
213 views

### ParallelMemberQ

I tried to make a parallel version of MemberQ for use with a large list, but failed miserably in terms of performance. I used Partition to subdivide the list and ParallelMap to perform the MemberQ ...
131 views

### Find all “chains” in the poset of divisors

I want to input a set of divisors of an integer $n$ and return all subsets of these divisors ${d_1,d_2,...d_k=n}$ such that $d_1$ divides $d_2$, $d_2$ divides $d_3$, ... and $d_(k-1)$ divides $d_k$. I ...