# All Questions

179 views

### how to find numerical zeros of $f(z)$ in a compact complex domain

I encountered a function $f(z)$ with several zeros in a region $1<\Re(z)<2, 3<\Im(z)<4$. These zeros are visible in a three dimensional plot like ...
65 views

### Fast functional method for multiplying duplication numbers in a large list

Consider a list of symbols: mySet = {a, b, b, c, a, b, c, d}; I would like to form the product of duplication numbers. In the example above, I have 2 ...
54 views

### How do I solve a profile interval (statistics)

I want to calculate a 95% profile interval for f0. Do worry too much if you do not understand what it is. I will illustrate with a simple example. ...
45 views

### Simplifying a fraction with bringing in new variables

Let's say I have a fraction like this: (a b x^2 + a^3 x) / (a^2 b x) and I would like to simplify it by multiplying both the numerator and the denominator with ...
81 views

### Plot function the uses Solve

Can someone tell me why I get an error (and how I get around it) from Solve while I try to Plot a function like: ...
267 views

### How to find out the current memory on the JVM?

I want to find out the amount of memory available in the Java Virutal Machine. I tried: ...
526 views

### Intersecting parabolas in an image

I have a friend who is a math teacher (like me) and while out cycling took this picture. The idea would be to create the equations of the quadratics that model the bridges and super-impose them on ...
129 views

### Something wrong with the way units are handled in V10

(This applies only to version 10) I obtain these two properties of silicon: a = ElementData[14, "CrustAbundance"] b = ElementData[14, "MeteoriteAbundance"] both ...
69 views

### SemanticImport::unexpinvaliderr error when using trial version

I am trying to use SemanticImport for a personal experiment. I can correctly import a tsv file from a path, but if I change ...
209 views

### How to pass options to ListPlot when using a DataSet?

Still learning the new DataSet feature, I would like to create a ListPlot where the color of the points is to be determined by a ...
166 views

### Problem with series expansion and integrate

I have the following very simple code. A power series in a-parameter, function f[x], is integrated with respect to x, and the ...
140 views

### Replace part in a matrix that matches specific pattern

I have the following problem. Given a matrix L which looks as follows, Matrix L is a link, route matrix. Further, I got the following vector (d), which indicates the demand per vertex combination. ...
76 views

### Plots are clipped randomly (almost)

I am experiencing a strange behavior in plotting a lot of functions. Basically, they are clipped within an horizontal range. Let try to run this code by varying nmax, it could be a problem of my ...
42 views

### Code/Exp Search Documentation Center Mathematica

I have added several of my own applications to my Mathematica documentation center. Currently Mathematica uses followings notebook options to help the user search for specific functions. ...
242 views

### How do I check to see if two expressions are equal?

This is what I am trying: (2 x - 2 Sqrt[x (x - v)] - v)/(2 x + 2 Sqrt[x (x - v)] - v) == (Sqrt[x] - Sqrt[x - v])^4/v^2 but it's not working. Can someone tell me ...
108 views

### WSMModelData Error

I am getting this error message when I run simulation in Mathematica that makes iterations to a SystemModeler model. ...
91 views

### Change in direction when a line hits an ellipse? [duplicate]

I'm trying to simulate reflecting light off an elliptical mirror. I currently store the ellipse in the form {center,{radii},rotationAngle} and the ray of light is ...
190 views

### Calculate expected value of piece-wise pdf

I have the following PDF of a random variable: $f(x)=\begin{cases} 1 & \text{if}\ \ \ 0<x<\frac{1}{2} \vee 1 < x < \frac{3}{2}\\ 0 & \text{otherwise}. \end{cases}$ How can i ...
96 views

### Zoom settings other than 50% 75% 100%, [duplicate]

Is it possible to choose a zoom setting other than what's provided at the bottom of each Notebook window (50%, 75%, 100%, 125%, 150%, 200%, 300%)?
202 views

### Ovals of plane curves (and esoteric surfaces in space)

Consider the curve $y^2 - x^3 + x=0$ with $x, y$ real. This curve has two connected components (one bounded, one not), and the question is: how do you get Mathematica to tell you that (if you do: ...
101 views

### Manipulating array

I have got an array like this: A = {{{1, 4, 5}, {3, 7, 15}}, {{5, 6, 9}, {7, 8, 2}}, {{9, 10, 1}, {11, 12, 3}}} I make differences in each sublist a following ...
172 views

### Mathematica multi-dimensional numerical integration default method

I'm performing multidimensional Numerical integrations with mathematica I was wondering what was the default method that mathematica was using. Also i'm changing some parameter inside the integration, ...
201 views

### Simplifying vector expressions

I have some code that calculates Jacobians, but the results contain terms that should simplify or cancel out, but I'm not sure how to achieve this. My code looks like ...
223 views

### Where can I find a good tutorial for stochastic modeling using Mathematica?

I am a newbie in Mathematica and I aim to use Mathematica mostly for stochastic modeling (to develop and analyze models in evolutionary biology). Note that I am not necessarily a great mathematician ...
67 views

Suppose that I have f[a_, b_, x_] := ... I'd like to create a list of n pure functions ...
170 views

### What is the PDF of a variable where a parameter is itself a random variable?

Question How do we analyze in Mathematica cases where a parameter in a Probability Density Function (PDF) varies according to another PDF? Consider the following example... Example The text below ...
195 views

### Solving Differential Algebraic Equations as BVP

I am trying to solve a set of DAEs. -4 \nu (\lambda(s))^{(-1 - 4 \nu)} \theta'(s) \lambda'(s) + (\lambda(s))^{(-4 \nu)} \theta''(s) = -\alpha_y \cos\theta(s) + \alpha_x ...
216 views

### Change the colour scheme in DensityPlots to make the zero white

We are trying to plot a density plot using the TemperetarueMap colour scheme. However, we don't seem to be able to make the white colour correspond to the value zero of the function we are plotting. ...
232 views

### How to use a Butterworth bandpass filter to generate a chirped signal [duplicate]

As there is no ChirpSignal function in Mathematica, I wrote a simple code to generate a sinusoid with a frequency that changes continuously from frequency ...
170 views

### C compiler error: the no library could be generated error

I have windows 8, Mathematica 9, and I've just installed Microsoft Visual Studio 2013 with update 3. I'm try to run Compile with the option ...
139 views

### Why the function cannot achieve the expected result?

Today, I write a toy code (Framed the prime in a list) to practice Mathematica programming ,which as shown below: Trail 1: ...
128 views

### How can I plot a list of 1-D data along the x-axis?

I would like to know how to create a graph from the following data: ...
353 views

### Pull out scalars from NonCommutativeMultiply in commutator of SU2 spin algebra

I am trying to work on spin chains in Mathematica. That is, N spin-1/2 on a one-dimensional lattice with periodic boundary condition (N+1=1). I need therefore the SU2 spin algebra $S_z, S_+, S_-$ with ...
276 views

### Uniform distribution on unit circle

I need a uniform distribution on the unit circle (x; y) : x^2 + y^2 <= 1 with the density f(x) = (2/Pi) Sqrt[1-x^2] ...
189 views

### How find solve the equation complex conjugate? [closed]

Tried solving it with every function I know but couldn't z*=z^2
129 views

### How to select states with equal times

Can anyone show me how to select the states that have equal times-dates. For example, i have two time series. First that have 10 observations, say from 2014/10/1 to 2014/10/10, and second that have 7 ...
50 views

### simplifying the range of two definite integrals

Today, I tried to obtain the solution of the following equation, sol = DSolve[ {m v'[t] + \[Gamma] v[t] == \[Xi][t] , v[0] == v0}, v[t], t] The solution, of ...
54 views

### How to increase the font size in PlotMakers

When I use PlotMarkers -> {\[FilledCircle], 40} in ListPlot I get something like this: How can I increase the font size of ...
111 views

### Strange integration

Bug introduced in 9.0 or earlier and fixed in 10.1 Note: Beginning with V10.1, this integral returns unevaluated but without error messages. I tried to evaluate this line ...
149 views

### GroupBy and MaximalBy to create a new Dataset

I'm looking for a neater way to achieve this, which to me looks awkward and suggests that I am missing something... Given a Dataset... ...
172 views

### Replace list of symbols in an expression

I have an expression: exp = a+b+c and a list containing all the symbols of my expression: syms = {a,b,c} and I would like ...
99 views

### Conditional combining of nested lists

I have two nested lists like those {{a,A},{b,B},{c,C}...{z,Z}} {{a,1},{c,2}...{t,12}}. I want to combine them to get a new list that looks like this ...
124 views

### NMinimize: Problem with constraints + Simultaneous minimization possible?

Introduction Dear all, I am fairly new to Mathematica. Recently I am trying to do the following: I have a function \textrm{hann}[t,t_g,n_m]=\sum\limits_{n=1}^{n_m}a_n\left[1-\cos\left(\frac{2\pi ...
220 views

### Finding the minimum vertex cut of a graph

Bug introduced in 9.0.1 or earlier and fixed in 10.2.0 Note: FindVertexCut is new in 9.0. It seems that Mathematica is not correctly finding the smallest set of ...
660 views

### Partial fraction decomposition of $1/(e^x-1)$

This link has discussion on finding partial fraction decomposition of $1/(e^x-1)$, so I experimented with Mathematica to see if M can do it, but looks like not. Similar is the case with one more CAS I ...
391 views

### Find the nearest locations for multiple points

Assume that there are many holes with their locations fixed, and the same number of balls distributed randomly. What is the smallest total distance for the balls fitting into the holes on the ...
108 views

### Exclude Infinite Value in Table

I'm creating a plot of a family of lines using their endpoints and plotting it like so: Graphics[Line[Table[{{x1, y1}, {x2, y2}}, {u, 0, 2 \[Pi], ustep}]]] Where ...
210 views

### NDSolveValue with a multiple variable equation

I'm trying to plot this equation of motion for a pendulum with a periodically applied torque for 20 cycles, where b, m, L, g are given constant values. ...