# All Questions

77 views

### How can I solve an equation independent of a variable? [duplicate]

Let's say I have the equation $$ax + b = 0$$ and I'd like to find a solution that doesn't depend on $x$, so here the solution is obviously $a=b=0$. I could solve this using ...
62 views

### Apply solution rules to new functions as parameters [duplicate]

Update: I put an screenshot of how my code and problem look like at the end. Say that Mathematica solved a system of equations and got two answers {{a -> 3, b -> c, d -> 0}, {a -> -3, b -> 0, c -> ...
117 views

### How to make program for phase portrait?

I need to add a phase portrait to my program. The program is below, and I need to create a graph like the one in the picture. My step size needs to be 5, from x0,y0 = 10 to x0,y0 = 50. ...
149 views

### How to extract numeric value?

Considering two situations: I have a string "F2.5" and Quantity["2.3s"]. How can the numeric value be extracted to have: ...
150 views

### How to properly interpret a seemingly contradictory result in Mathematica?

I have a problem with interpreting the results of my notebook outputs. It is important that I do not err with the interpretation. Here is the full input: ...
187 views

### Parallel and non-Parallel functions return different results?

A friend of mine observed that when running ParallelMap or ParallelTable that he would get different results than when running ...
54 views

### Generating terms of the Stirling series

The Stirling series starts as follows: $$n!=\left(\frac{n}{e}\right)^{n}\sqrt{2\pi n} \Bigl\{1+\frac{1}{12n}+\frac{1}{288n^{2}}-\frac{139}{51840 n^{3}}-\frac{571}{2888380 n^{4}}+O(n^{-5})\Bigr\}.$$ ...
161 views

### How to get rid of the background tiny crosses when using Graphics?

I am plotting very tiny arrows. For large arrows there is no problem but for small ones, one can see little crosses in the arrow positions. I do not want to see this crosses. I just want to see no ...
49 views

### How to trim out sequence of blank-spaces?

Considering we have few strings: s1 = "dasbdk " s2 = "asdnkal asn knkl nkn dvklsn " s3 = " jbjkbasd nklnkln " Q1: How can the blank-spaces in ...
19 views

### Protected Tags Error [duplicate]

While trying to run this piece of code: ...
61 views

### How does one initialize large arrays in Mathematica with a structured format? [closed]

I want to create a 10 by 10 matrix that increases by 1 every unit across like: 1 2 3 4 5 6 7 8 9 10 11..... Is there a function that does this without having ...
39 views

### Changing arrowhwead size and other parameters when plotting vector fields

When plotting vector fields how to keep arrow head size constant, have the arrow LENGTH proportional to the MAGNITUDE of each vector, change the thickness of the vectors (but keep this constant) and ...
61 views

### Retrieving forthcoming step size from NDSolve

I'm solving a system of ODEs with a random component, which changes at each calculation step and depends on the step size. So I'm trying to realize something like this: (1) size of the forthcoming ...
70 views

### Plotting two parametric regions together

I have the following code below, which allows me to plot two nice figures in the plane. ...
47 views

### Problem with plotting a function that calls FindRoot

I am having difficulties in plotting the solution of FindRoot to solve 4 variables. I defined a function and then tried tp plot it, but got an error message ...
179 views

### How can I understand this short example?

First launch kernels LaunchKernels[4] {KernelObject[5, "local"], KernelObject[6, "local"], KernelObject[7, "local"], KernelObject[8, "local"]} Then I calculate ...
92 views

I must advise you that I am an almost total novice in mathematica.. However here is my very simple question.. I know the command FindMaximum[{f},{x}] to find the maximum point and maximum value of a ...
53 views

### Slider for different plots

Hi I've got 12 different plots and I want to be able to cycle through them with a slider, however, none of the options for manipulate or slider seem to be able to handle multiple plots. My parameter ...
104 views

### Challenging matrix sorting request?

I have an application in mind, and I need to do the following analysis, but am having a high degree of difficulty conceptualizing it in terms of syntax. I understand what I want, but cannot seem to ...
33 views

### pass fail criteria as legend in histogram and plot

I have a random data and want to plot the histogram with specific bin ranges. Each value of data[[x]] is actually [(data[[x]]*2.2)/4] with units as microns; where 4 is the magnification of microscope ...
60 views

### How to synchronize control of two dynamic variables? [closed]

My ideal implementation will be like if you click the slider that labeled with "frequency",the content of the text grid will change synchronously with the wave function. However,I couldn't bind them ...
78 views

### How can I include functions from a package into a CDF file?

I am building an application which I would like to deploy as a CDF file, and I am struggling to make the CDF exports work correctly with functions pulled from a .m package file. What are good/best ...
23 views

### Simplify trigonometric equation [migrated]

$$\alpha sin\theta + \beta sin\phi + \gamma sin(\theta+\phi) = 0$$ where $\alpha, \beta, \gamma$ are constants. I want to simplify this into a linear relation between $\theta, \phi$ I wonder if ...
70 views

### Problem with “Lighting” in Mathematica V9

I am showing two figures with Show: ...
126 views

### Why does DSolve return two solutions for my ODE?

I wanted to solve the differential equation: $y’ = (1+2x)\sqrt{y}$ with $y(0) = 1$. It can be done by hand, and to check my answer I typed the following in Mathematica ...
44 views

### Move figures inside function Show

I have a ListLinePlot and a ListPlot3D that I want to combine using Show. I do not know how to change the positions of the figures. Here a toy example: ...
52 views

### Plotting the Solution of a Parametric Differential Equation [closed]

I have a parametric differential equation: sol = ParametricNDSolve[{a p[t]/(1 -b p[t]) == c p'[t], p'[0] == 0},p,{t, 0, 10}, {a,b,c}] How can I plot the ...
47 views

### Transforming an Optimization Problem into a multi-vector Optimization Problem

I am sitting on an MultiAgent optimization problem trying to solve for a quadruple of variables {e,l,b,c} In a single agent (...
39 views

### Can Manipulate parameters be hidden with an If statement? [duplicate]

I'm making a demonstration with the following code: ...
53 views

### Strange behavior of FourierSinCoefficient

FourierSinCoefficient works normally like this and the result is checked with Integrate. ...
28 views

### Color Gradient on points using ErrorListPlot

I am having some difficulties getting a value-dependent color gradient on points with ErrorListPlot. I am starting with a list looking like ...
64 views

### DateListPlot in webMathematica doesn't show FrameTicks properly

It seems that DateListPlot when used in webMathematica (3.3.1) show different output than in desktop Mathematica (10.1). In desktop Mathematica, if you evalutate ...
26 views

### Where can I find books about how to use Mathematica solving practical problems? [duplicate]

I can use Mathematica solving commman maths problems like Calculus,Linear Algebra and visualize functions.When I want to improve programming level,I find that most tutorials out of practical ...
1k views

### What are the Wolfram Language's relative strengths for machine learning?

I see a low use of Mathematica in Kaggle competitions. Why would one use the Wolfram Language versus R, Python, or Julia for machine learning? Besides prettier plots and the Manipulate function, ...
74 views

### Animate an object in 3D given by six lines [closed]

I have a structure defined by six line segments connecting six points. The coordinates of the six points change with time. Each coordinate has a formula giving it as a function of time. Three of ...
127 views

### Why can't Mathematica DSolve my equation? [closed]

I am trying to solve $\begin{cases} v(t) = A \cdot e^{kt} \\ v(t) = s'(t) \\ s(0) = 0 \\ v(0) = A \\ v(6000) = 299792458 \\ s(6000) = 2.37 \cdot 10^{16} \end{cases}$ for $A$ and $k$. But neither of ...
64 views

### How to define an expression which is differently evaluated in calculations and printed

Let's say, we have a list: values = {1.2, 0.04, 0.9}; Is it possible to replace 0.04 by some expression, which displays as ...
170 views

### Failure in integrating from an interpolating function!

Consider a list like below: ...
147 views

### Rule transformation between letter and number

I have a global rule as follow: ...
333 views

### Is FrameTicks broken in 10.1.0?

On my system, Mathematica 10.1.0 under Windows, none of these FrameTicks documentation examples work correctly: ...
32 views

### AltGr randomly stops working - Windows 7

My problem is that AltGr just randomly and frequently stops working. I've only seen this problem since the last update (10.1). The only sure way to recover functionality that I've found was to change ...
24 views

### How to adjust the FrameTicks length in DateListPlot?

suppose I have the data for DateListPlot: ...
34 views

### Covariance matrix estimation when number of variables is larger than number of observations

It is well known that the sample covariance matrix estimator results in a singular matrix if the variables is larger than the number of observations. One solution is to apply shrinkage estimators. ...
76 views

### How to define $x^n$ where $x=\pm 1$ and $n\in\mathbb{Z}^{+}$?

I do not know how I can define $x^{n}$ in Mathematica, where $x=\pm 1$ and $n=1,2,3,\ldots$. For even values of $n$ we simply have that $x^{n}=1$. While for odd values of $n$ we have that $x^{n}=x$. ...
17 views

### log as paremeter to my defined function [closed]

integrateAsSum[function_, beggining_, end_] := Sum[function[i], {i, beggining, end}] integrateAsSum[log, 1, 3] (* log[1] + log[2] + log[3] *) As you guys can ...
74 views

### speed up evaluating a listable function

I apologize in advance for the vagueness, but I can't think of a more descriptive title. I am trying to find the average value of the square of BesselJ[0, x] ...
166 views

### Exporting Dataset to WDX format fails

I reported this to WRI support. Tracking number is CASE:3368636 Official answer is: Thank you for contacting Wolfram Technical Support. This is a known issue and our developers are working on a ...
42 views

### Importing a spreadsheet with infinity values from Excel

I have imported a spreadsheet from Excel that I want to use as an adjacency matrix. I want to use this matrix as the argument in WeightedAdjacencyGraph, so I have ...