# All Questions

51 views

### Inverse Z Transform returning complicated expression

I want to study how the Z transform changes with the sampling rate T, in a closed loop system. The command I'm using to do this is: ...
787 views

### Fast code to generate large random graph with fixed degree sequence

I'm trying to create a function so to generate large random graph with a fixed degree sequence $\{v_1,v_2,\dots,v_N\}$, where $N$ is the number of vertices in the graph. The Mathematica function that ...
80 views

### Running function - updating list - run function etc

I am making a larger program, so I would prefer to give a short example of my problem: ...
171 views

### Index of iteration inside NestList [duplicate]

I have a list of RandomReal: delta = RandomReal[{-0.01, 0.01}, 1000] I want to add each element of the list to the ...
435 views

### Why IntegerPart[x/(x/2)]=1?

Consider this code x = 0.109354682484; IntegerPart[x/(x/2)] (* 1 *) Precision[x] (* MachinePrecision *) Why does it give 1 ? Version number: 9.0 on Mac 10.9.2 ...
67 views

### Variable location for intial value in ParametericNDSolve

I am trying to figure out if Mathematica allows a variable location for a known initial value for ParametricNDSolve. I haven't been able to find an example where ...
102 views

### Determining sample size with no replacement for a given confidence and reliability when there are x failures observed during sampling?

I am trying to follow the procedure of a Sandia Labs report found here to determine the required sample size, for various population sizes, with no replacement for a given confidence and reliability. ...
117 views

### 2D Plotting of triplet data set with third axis as variation of thickness of curve

I have similar question like mentioned at representing triplet data set with color on 2d plot but this time instead of color I need to represent variation of third axis with the thickness of the curve ...
86 views

### Customize TableForm behavior for a single function

I have a function of this form Garch[a,b,c....] that gives me a list as an output,where the first column collects names of output variables. Is it possible ...
86 views

### Locate Blow-up in NDSolve with Whenevent

At some point I get this error: ...
73 views

### .NET link - index of property

I have a property in .NET Type, which is actually a generic list of objects. When I try access the property using numeric index e.g. 10, this works. However when I iterate through indices using ...
254 views

### Plot Wiener Process and its running maximum

I want to plot a Wiener process $B=(B_{t})_{t≥0}$ and its running maximum $S_{1}=\max_{0\leq t\leq1}B_{t}$ on Mathematica. Can anybody help? I only know how to generate a Wiener process using ...
75 views

### How can I do symbolic vector differentiation in mathematica? [duplicate]

I want to do this calculation using Mathematica and I do not know how. I want to finf gradient of a vector function I Have this $$f:R^n\to R$$ $$\nabla_xf(x)=\nabla_x(x^tBx)$$ I want to get ...
264 views

### How to restrict the mouse cursor to stay within a box?

I'm trying to use Mathematica to write small games, and I find that it would help to restrict the player's mouse into the game window (just like other games do). Is there any way to achieve this? ...
166 views

### Incorrect evaluation for Thue-Morse signed harmonic series

I would like to evaluate $$s = 1 - \frac{1}{2} - \frac{1}{3} + \frac{1}{4} - \frac{1}{5} + \frac{1}{6}+\frac{1}{7}-\frac{1}{8} - ... + \frac{(-1)^{\textrm{binary digit sum}(n-1)}}{n} + ...$$ where ...
129 views

### ListContourPlot memory problems?

I have a simple 3d dataset (size 7035 x 3, I put it on my site if you want to check) which I want to plot with ListContourPlot: ...
114 views

### Problem with Label in a Do loop, “nolabel” [closed]

Can someone tell me why this code doesn't work and how to fix it ? Thanks. ...
39 views

### Sending a command to an already opened frontend

I'm trying to pipe low-level notebook commands to work through terminal and I've tried various ways, but I can't really get to the frontend that's already open. For example Opening a notebook from ...
89 views

### How can I add a logo to a presentation?

I am trying to make a presentation with Mathematica and would like to know if there is a way to add a logo that will show in every slide. I have not found any settings that would allow me to do that ...
142 views

### Slot (#) interfering with evaluation

In the following I am using one function makeFunc to assemble two functions a[t] and b[t] to ...
188 views

### How to update a list in a function in each iteration

There is a list with numbers 1 to 8 ( p1 ) and another list (j) which contains 4 numbers which shows different 4 positions of ...
78 views

### Identifying and isolating sections of overlap in a set of integer intervals

I have a very large array like the following: {{1,10},{8,9},{9,20},{34,40},{41,42},{43,50},{47,53},...}; Now, imagine that every element in the array corresponds ...
261 views

### Monte Carlo integration with random numbers generated from a Gaussian distribution

I want to do numerical integration of some functions using the Monte Carlo method. The default setting for the Monte Carlo method is to use a uniform distribution as far as I know. How can I change ...
157 views

### Highlighting or coloring certain words / substrings appearing in a larger string

I have one longer string, longString, and a set $S$ of shorter strings {ss1,ss2,ss3,...}. I'd like to print out ...
216 views

### Deleting all characters in a string that do not belong to a small set of elements

Say I have a string {100 aa bbc%j%b%wa ajjcj11j0%2wj fc} with a lot of undesired characters or spaces in it, for example: {" ", "%", "w", "j"}. I'd like to strip the string of these characters, with ...
331 views

### Display a labeled multigraph

Introduced in version 9, fixed in version 10. Thanks Szabolcs for providing this screenshot showing that the bug is fixed. Despite the integration of graphs and networks, multigraphs are ...
150 views

### Shrinking the size of exported 2D density, vector field, and streamline plots

My question concerns the size of exported eps files that were created using density, contour, vector-field, and/or streamline plots: these files are so huge that whenthey are are inserted into a ...
381 views

### What is the mathematical meaning behind D[f]?

y = a + b x; I can understand this output of the ordinary differentiation of y w.r.t. x ...
316 views

### Finding All Chordless Simple Cycles In A Graph

I am doing a research on networks which consists of polygons with different number of sides. I am trying to find all simple cycles in a network which are chordless. As an example, consider the ...
60 views

### Manipulate AnimationRunning equivalent?

I have a Manipulate function with two variables. I would like one of them to begin autorunning immediately once the function is evaluated, but the other to remain ...
552 views

### Anti-aliasing a fractal-like bitmap image

I have a .bmp image 9600x5400 that shows a lot of points at various intensities. There are no lines inside this picture - only a lot of points. I would like to apply anti-aliasing on the image to make ...
295 views

### Plotting solutions of a 4th order polynomial equation

I have a polynomial equation of the fourth order, which has $4$ roots depending on a variable parameter s1. For each s1 I have ...
73 views

### Multiple scripts run using same kernel

I have an external program that calls Mathematica scripts upon certain events. Each script requires a large Mathematica library to load (takes a while). Is there some way to run an initial script ...
31 views

### RandomReal behavior in Block environment [duplicate]

I ran into an unexpected behavior of RandomReal function inside the Block environment. If I simplify my problem: I wanted to use two random local variables, such that the second one would be less that ...
70 views

### How to simplify or improve my code (or how to Flatten inside the matrix)?

I believe that it may be simplified, but I have no ideas anymore.. I need to flatten inside each element of array. F.ex. {{1}, 128552, 6, 1} ---> {1, 128552, 6, 1} Input data (Z - requests, t - ...
103 views

### NDSolve accuracy related problem

I want to solve this equation: ...
125 views

### Problems with BSplineFunction vs. BSplineSurface

Why are those surfaces different? ...
115 views

### DateList does not output the correct time, but Date does

I noticed a strange thing when trying the new astronomical data functions in Mathematica 10 on my Raspberry Pi. The Sunrise and ...
177 views

### How to combine matrix with array without cycles?

I am new to Mathematica. And I'm sorry for my English. I have created a matrix ($6 \times 4$) and an array ($1 \times 4$). I want to get another matrix that will have the first element from the array ...
110 views

### How to generically produce iterators (to loop over many variables)

A generalization of, for example: Do[(* stuff *), {x, listx},{y, listy},{z, listz}] I can almost do this with Table, but I need a way to flatten the outer ...
135 views

I use Apple's Numbers spreadsheet for a single thing, a double entry accounting model to understand complicated financial transactions. A current model depends on the value of a single initialization ...
88 views

### Ordering for Pattern matching in Subscripts

I have some transformation rules acting on subscripted variables. When I match the a product the order matters. ...
482 views

### Image processing: extracting ordered contour

Continuing the question How to extract the edge from a set of points and its answer by Simon Woods, I would like to ask if there is a way to extract the boundary of obtained as ...
157 views

### Impose an specific Trigonometric expansion with TrigExpand

Is there a way to impose in mathematica an specific trigonometric expansion with TrigExpand? I have various double-angle expressions for cosine and sine in my ...
177 views

### BVP system of nonlinear coupled ODEs

Here I am, trying to solve this system of coupled ODEs (up to a minus sign): $u''=6u^5-(8+4a)u^3+(2+4a)u+\frac{2u((w^2-s)^2+bw)}{(u^2+c)^2}$ $w''=\frac{4w^3-4bw+b}{u^2+c}$ with the boundary ...
149 views

### How to preserve the order of terms in the output

Is there a way in which mathematica can preserve the order of operations while it evaluates an expression?, for instance: In my short example ...
174 views

### show fit information on plot

After performing a fit in Mathematica, I would like to show the fitted parameters in a box on the plot showing the fitted function. How would I go about achieving that? Here is a MWE: ...
65 views

### using deletecases for twittermessages using the timestamp

I have a Excelsheet with tweetsmessages. These tweets are all written in Dutch. I would like to analyse these tweets in relation to the timestamp. ...