# All Questions

28 views

### Need help with GRE study question [on hold]

I encountered a question while preparing for GRE and am stuck. In an examination paper of 5 Questions, 5 percent of the candidates answered all of them and 5 percent none. Of the rest, 25 percent ...
35 views

### Equation of a transformed ellipsoid

How do I use RotationTransform to transform the ellipse with respect to the y-axis? The origin of the ellipse has to be at a length of ...
32 views

### Matching a case when one element in a pair is Null

I've got a dataset of laitutdes and longitudes. Unfortunately, some of the dataset was from when a time when lat/longs weren't constantly recorded. So I need to remove the invalid data before working ...
33 views

I want to solve some equations in Matlab which i generated with my code in Mathemetica. I want to convert these simple equations to matlab code and try to solve them. I am trying to download ...
25 views

### Restrict plot of object to be below a given plane in a ContourPlot3D

In a ContourPlot3D, I only want to part of the plot. Such as the part of a cylinder that lies beneath a plane. ...
26 views

### ParametricPlot MeshStyle bug in v10?

The documentation gives the following code and says "Use a red mesh in the x direction and a blue mesh in the y direction:" ...
23 views

### Problem with Neumann condition in quarter disc

So I'm following the available examples in version 10 for FEM, The plane stress operator is shown as this ...
29 views

### Calculating Value-At-Risk (VaR) in Mathematica. A simple code [on hold]

Calculating Value-At-Risk in Mathematica Obtaining data (Microsoft. Daily returns 2014): msftreturn = FinancialData["MSFT", "Return", "2014"][[All, 2]]; Code: ...
43 views

### Functions in functions

I have three functions f(x,y) , g(t) , and h(t) and somehow I have to find (d/dt)f(g(t),h(t)) where t = 0. How would I go about writing this in Mathematica? In this equation g(t) is taking place of x ...
96 views

### Solving 4 variable system of equations

Trying to solve a systems of equations. Here's the code: ...
40 views

### Problem with Style in a Plot

I would like to simply plot a density function $f_1$ and I would like to put a legend but I cannot do it as I wish. The problem is simple but I spent alot of time and couldnt solve it. I will be happy ...
24 views

### Changing working precision to 10 in NIntegrate introducing error messages and giving bigger error than precision 5

I have two numerical integrals as follows: ...
32 views

### Automatically to add some points for a plot

Say I want to plot this Plot[x,Sin[x],{x,0,4 Pi}] And I want it to show 4 nicely spaced points, on the line. Is there an automatic way to do this? I was reading ...
29 views

### Struggling with FindFit

I'm trying to fit a sinusoidal wave to some numerical data. I can do it by hand using manipulate, so I know roughly the sort of parameter values that I should get back, but functions such as FindFit ...
34 views

### Taylor Polynomials and Approximations in Mathematica [on hold]

I have to solve number 112 parts a, b, and c and number 113 parts a and b using Mathematica. I am very new to Mathematica so any and all help would be greatly appreciated. Click the link below to view ...
16 views

### To UpSet or not to UpSet when using MakeBoxes

What is the difference between the following two: ...
27 views

### Truncating power series

I have the following typed up so as to truncate higher powers of $\tau$, ...
17 views

### Define a Recurrence Table involving other tables

I'm relatively new to using Mathematica. Previously I used Matlab, but lately I noticed that the numbers i got in both of them do not match (mostly it seems that Matlab lacks precision...). The ...
31 views

### Turning a 2D 3 body problem into 3D not so easy?

I have programmed a 3 body problem, that can in theory work for more than 3 bodies. I apologize in advance for the length of the code that I posted, I don't really know how much one would need to ...
72 views

### ListPlot inserts extra PlotMarkers and Mesh at crossing points

In the example below, ListPlot with PlotMarkers -> Automatic and a variant using ...
53 views

### Is there a way to stop Export if the file size is too big?

I've got code that's exporting a file, but the file might be so big that it will take up too much space on the cluster I'm using and crash other users' processes. Is there anything like ...
42 views

### Identically styled cells from ToBoxes and Cell do not align

I'm trying to generate some worksheets using NotebookWrite so that I can control the page breaks, but have got stuck on the alignment as there appears to be a ...
204 views

### How do I generate cross sections of a 3D graphic?

I would like to approximate the volume of a bottle by summing up the volume of the individual disks. I have obtained code references from a demonstration. But how do I generate the cross sections? The ...
71 views

### Mean curvature of Sphere

I am trying to calculate mean curvature of a parametric surface(like sphere), and I wrote this code based on this discussion. Here is my code: ...
169 views

### Plane Geometry Diagrams With Labels

I can make some basic diagrams in Mathematica (stolen from their pages, for example see the below: LaminaData["FilledIsoscelesTriangle", "Diagram"] However, I'm ...
46 views

### How to calculate minimum positive solution of a equation?

Equations with triangular function usually have multiple solutions, like Solve[Sin[x] == 1/10, x] returns a solution like ...
62 views

### Problem using Compiled Function within NProbability

I've built a very simple function to estimate the probability for a Long Straddle (derivative strategy) to be positive at expiration. ...
38 views

### How to make an effective use of Mathematica to evaluate integrals, series, recognize closed forms, and do other manipulations [on hold]

I would like to know if there are resources to learn how to use the functions of Mathematica in the most effective way in order to evaluate difficult integrals and series or find possible closed forms ...
38 views

### How can I stop the integration of NDSolve with a condition?

I try to solve a partial differential equation by NDSolve. At some point, I want to stop the integrating by a condition that compares the min value of the function ...
104 views

### Apply Trig Identity to Transform Sum of Sinusoids into Phase-Shifted Cosine Function

I'm trying to solve for the output of a simple RC low-pass filter, with Cos[w t] input. The convolution of the input with the RC transfer function gives me the right output, but I'd like to be able to ...
76 views

### What is the algorithm behind Mathematicas Reduce in this equation?

Mathematica can use Reduce to arrive at an answer in this equation ...
86 views

### Unable to DSolve[{x''[t] + x[t]^3 == 0}, x, t] with IVs

I tried to solve for an non-Hookean spring's motion, but the output from Mathematica is weird. It seems that there is inverse functions involved. ...
67 views

### Mathematical operation on two lists by a “key” [duplicate]

I'm a complete newb here. Just looking for direction. I've got two lists like this... ...
16 views

### Size and Power of Test: Poisson Distribution [migrated]

In a homework problem, I am given a Poisson distribution with lambda = 1 as null hypothesis, lambda greater than or equal to 2 as an alternate hypothesis, and 3 as a test statistic. I am instructed to ...
60 views

### Image background subtraction using parallel computing

I am developing a program for pattern recognition. I want to use the parallel computing to get a real time application. I have two cameras where each one gives n frames/second. I need to process the ...
64 views

### Derivative of an expression containing a symbolic sum [duplicate]

Is there a general pattern for working with symbolic sums in Mathematica? For example here's a derivative I want to compute: ...
144 views

### Plotting two recursive functions

I'm trying to plot two recursive functions (p and θ) on a map. So far I have: ...
42 views

### Rationalize complex numbers

What is the best way to rationalize complex numbers, if not both the real and imaginary part are actually rational? According to the documentation, Rationalize ...
131 views

### Plotting on the Raspberry Pi

I just now powered on my new Raspberry Pi for the first time and tried the supplied Mathematica (Wolfram Language). One thing I tried was Plot[x, {x, 0, 1}] ...
47 views

### How to use Tandem Queueing Network Process?

Mathematica provides QueueingNetworkProcess and QueueingProcess. However, I can't seem to figure out how to create a tandem ...
43 views

### How to tell Eigensystem the type of the elements comprising a matrix I would like to diagonalize

How can I tell Eigensystem that a matrix $M$, which I would like to diagonalize, is a numerical matrix of complex numbers? My idea is that this information could ...
50 views

### Unexpected behavior from Indexed

I was going to include Indexed in this answer, thinking that it operated much as a List-only ...
27 views

### a complicated Sum [migrated]

I don't know how i can calculate this complicated multivariate sum : $$S(l,k)=\sum_{|m|=k} s_{l,m}=\sum_{|m|=k} l(l-1)(l-2)\dots(l-m+1)$$ Where $m=(m_1,\dots,m_n)$, $l=(l_1,\dots,l_n)$, and $k$ a ...
49 views

### Solve Linear Programm [on hold]

I got the following LP problem and have to solve it. Obviously, the y in the objective function needs to be replaced by constraint 2. These are the current values for H,L,f. Any ideas, how I can ...
113 views

### DSolve returning { } when given my ODE

Why does this code return {}? ...
51 views

### Summing subsets of array

I have an array farr, size Nx*Nx. I have a function frk that maps index {n,m} to an integer (approximately ...
35 views

### Loops for Unit Root Test

I want to compute some unit root tests on a data generating process. I already split the sample in 100 single samples, but how can I do a unit root test on all of them and store the results in another ...
118 views

### Extracting coefficients from a power series

I have a function defined explicitly as a power series: $$\sum_{n=0}^\infty{T_n}\frac{x^n}{n!}=\frac{\frac{x^3}{3!}}{e^x-1-x-\frac{x^2}{2!}}$$ and I would like to extract the coefficients $T_k$ as ...