# All Questions

42 views

### How to fit ODE's coefficient, just like using NMinimize [duplicate]

I want to fit ODE's coefficients to a model. I tried using NMinimize, but it seems it does symbolic instead of numerical calculations. ...
134 views

### BezierCurve in EdgeShapeFunction fails when used on multiedges graph

I would like to create a network graph with curved edges. To do this, I wrote this function: ...
137 views

### How to plot complex values given by Solve

Update Solve[N[Table[BernoulliB[n, z], {n, 10, 10}] == 0]] ...
195 views

### Formatting plot of symmetric points differently to asymmetric points

From an array of numbers, I would like to determine (and then colour appropriately) which points are symmetric about a given axis (here, $x = 1/2$), and which are not. For example, form this: ...
129 views

### Compute coefficient of Generating function

Given a generating function $F(z)$, is there any way to compute the coefficient $a_k$ of $z^k$ by Mathematica? One method is to calculate by the equation $\frac{F^{(k)}(0)}{k!}$. However, this ...
80 views

### There is a button in the “basic math assistant” which wraps highlighted text in chosen brackets. Is there no keyboard command for this?

This counts as something of a basic question, but one for which I cannot find an answer. I checked the documentation, I checked google, I searched it here, I read a bunch of different things, but ...
168 views

### Differentiating a Cumulative Distribution Function which has a discontinuity at $0$

I want to take the derivative of a distribution function which has a discontinuity at $0$. Here is the function: ...
206 views

### Compatibility issues for Combinatorica package

I am trying to use the Combinatorica package in a Mathematica version 9 in the following code : ...
130 views

### Assumptions in mathematica when Symplify on Log[Exp[a/b]]

In mathematica 9.0: This: Assuming[b > 0 || b < 0, Simplify[Log[Exp[a/b]]]] yields: a/b However, this: ...
222 views

I want to add two matrices, the first one containing a 2D vector at each position the other one a list of 2D vectors. The 2D vector from the first matrix should be added to each of the 2D vectors at ...
194 views

### What is the formula for this numerical series?

I'm developing a questions game. My goal is that the score for each correct answer will increase as the user answers more questions. Initially there are 15 points for each correct answer. Every 4 ...
499 views

### How do I place a texture on an irregular 3D model?

I'm trying to reproduce a textured head in Mathematica, and I'm using a kind of 'net' of a head which contains all the features on the face. The texture looks like this: which is supposed to look ...
48 views

### Parallelizing an associative binary operation

I have an associative binary operation '.', which I often use in this sort of way: result = expr1 . expr2 . expr3 . expr4 The ...
298 views

### Finding maximal sublist of linearly independent vectors

Given a list of vectors v = {v1, ..., vn}, which is the fastest way to find a maximal sublist of linearly independent vectors? I could add the vectors one by one to ...
414 views

### 10bits per rgb / 1024 shades of gray?

Can we display 10 bits per rgb in Mathematica? I'm using a quadro card and 30 bit monitor and can get a smooth gradient using Psychtoolbox in matlab. The following Mathematica should produce a bar ...
206 views

### Group list of lists by Total

I have some list which looks like {{0,1},{4},{0,0,1},{2,0,1},{3,0,0},{3,1},{0,0,0,4}} and I need to group lists with equal sum of elements in ascending order ...
103 views

### Histogram For Non-Numerical Data

I have a non-numerical data, let say data = Table[RandomChoice[{0.2, 0.3, 0.25, 0.15, 0.1} -> {"A", "B", "C", "D", "E"}], {500}]; and i want to make a ...
210 views

I have a function of two variables $f(r,x,c)$, where $r$ and $x$ are variables and $c$ is a constant that appears in the function. I would like to write it as a product of two functions $f1(r,c) ... 3answers 322 views ### Flow in pipeline graph I have pipeline directed graph which has one source and several sinks ... 1answer 163 views ### Plotting Laplace's equation on an infinite domain I am trying to plot my solution to a Laplace equation on an infinite domain. However, when I try to plot it, Mathematica just runs with nothing happening. ... 1answer 216 views ### Limit of sequence of functions behaving strange I'm trying to determine the limit of the sequence of functions $$f_n(x)=\left(\frac{1}{\pi}\arctan(n x) + 1/2\right)^n.$$ I define ... 3answers 166 views ### Simplifying expression with patterns (Replace) Q1: I need to simplify some algebraic expression, according to particular pattern, namely: \begin{equation*} x^m = \left\{ \begin{array}{ll} 1 & \text{if } m \text{ is even} \\ x & \text{if ... 1answer 80 views ### Whitespace after number subscript When I write something like this: (Subscript[x, 0], f(Subscript[x, 0])) I get some undesirable whitespace after each of the ... 2answers 261 views ### Organise a graph's vertices into levels I would like to organise a graph's vertices in levels. Consider ... 0answers 88 views ### How to capture implicit fails in Plot or Show? [duplicate] How can I make a construct similar to C++ functions: try{} catch{} I want to use it to avoid showing a lot of errors in the plot area when for example one of the ... 2answers 365 views ### KolmogorovSmirnovTest[] On Frequency Data I have two observed frequency data, let say f1 = {100, 200, 150, 100, 50}; f2 = {110, 195, 160, 105, 40}; and i want to know whether these random samples belong ... 2answers 147 views ### How to increase the size of the dot produced by OverDot[] As the title says, I want to find a way to increase the size of the dot produced by OverDot[]. Here is a simple code ... 1answer 170 views ### Plot Ticks disappear when combining Plot with Graphics I'm attempting a simple Plot that I want to add asymptote markers to: ... 1answer 559 views ### Syntax question regarding Triple Integrals in Mathematica Integrate[1, {z, 0, 5}, {x, -Sqrt[ 9 - y^2], Sqrt[ 9 - y^2]} , {y, -3, 3}] 60 Sqrt[9 - y^2] How comes I am not getting a number for my final answer? This ... 4answers 216 views ### Given an implicit solution, how to plot transformation of this implicit solution? I have a function, which gives an implicit solution of a variable$y$as a function of$x$. Moreover, I have a function$f$which depends on$y$. How to plot a ratio of$f/y$, given that$y$is only ... 3answers 780 views ### Convert Integer to Real Is there a preferred way of converting an Integer to a Real? What I'm using at the moment is ... 1answer 106 views ### Memory usage of timeseries - lists of {Integer32, Real32} A list of {Integer32, Real32} items in Mathematica seems to use 12-times as much memory than the C equivalent array of structs. ... 2answers 4k views ### How to calculate contour integrals with Mathematica? How to calculate the integral of$\frac{1}{\sqrt{4 z^2 + 4 z + 3}}$over the unit circle counterclockwise for each branch of the integrand? 2answers 146 views ### Write list of polynomials as a matrix of coefficients times a list of monomials I have the following problem: given a list of polynomials P = {p1, ..., pn} on the variables x[1], ..., x[n], find a list of ... 0answers 97 views ### Programming a Meijer G related result I am not that new in Mathematica, but I do not remember I have ever used it for programming (like we may do in Java). I have an important result given here by this integral:$$\int_0^{+\infty} ... 1answer 70 views ### Unequal and Compile ... 1answer 159 views ### MapThread and Compile After discovering that MapIndexed cannot be used with compile (see MapIndexed and Compile) I am now trying do implement similar functionality using a combination of ... 0answers 1k views ### How to assign (and retrieve) variables with subscripts? [duplicate] I like to give subscripts to my variable names when the variables are related. I.e., Subscript[r, i] = 3 3 A problem arises when I later assign ... 3answers 201 views ### Product of edge weights in path I need to calculate the product of graph edge weights on the path taking into account edge direction. I.e. for graph ... 1answer 212 views ### Why is D[a[b][c],a[b]] equal to 1[c]? Background: I had the same issue as described here, and I went to extend Mr.Wizard’s code such that a[b][c] would be shown as$a_b^c$. Issue: To my surprise, ... 4answers 145 views ### Rearrange graph I have to rearrange graph described by j = {1 -> 2, 2 -> 3, 3 -> 1}; appling some function to all vertices on the right so rearrange[j] output should ... 1answer 124 views ### Set defaults for ViewPoint and AxesLabel Instead of adding AxesLabel -> {x, y, z} every time to code in order that the axes appear, how can I make Mathematica display the axes by default? Also, how can ... 1answer 4k views ### Plot points, line and plane in one 3D plot [closed] What's the easier way to plot these coincidently in 3D: ● The plane$5x - 4y - 9z = 0$● Parametric line$x = t, y = t/2, z = t/3$● Two points:$(0, 0, 0), (1, -1, 1)$? Moreover, how can I pick ... 2answers 171 views ### Write 199319989756262759279209 = 5x + y, where x and y are integers$\frac{199319989756262759279209}{5} $=$ 3.9864\times 10^{22}$according to Mathematica, but I would like to see this number exactly in decimal form (not in scientific notation). I'm attempting to ... 1answer 459 views ### Hatched bars and bar-specific background in BarChart I would like to diagonally hatch the bars in BarChart and to have three different background colors for the different bars, like this: Any ideas how to ... 3answers 110 views ### Make all the lines equally sharp [duplicate] Graphics[{ Line[{{# - 1, -0.5}, {# - 1, 5.5}} & /@ Range[6]], Line[{{-0.5, # - 1}, {5.5, # - 1}} & /@ Range[6]] }] There are two kinds of lines in ... 1answer 224 views ### ReadList can't read correctly I'm trying to load some data into Mathematica from some files generated by fortran. But ReadList seems can't get the number correct. Here is a simplified version of the problem: ... 0answers 106 views ### Solving for$d$in$x= E^d mod(n)\$

With regards to Public Key Cryptography, I have been tasked with the problem of attacking some information given in an assignment and discovered a private key used to digitally sign a message. Known: ...