0
votes
0answers
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. ...
4
votes
2answers
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: ...
2
votes
2answers
137 views

How to plot complex values given by Solve

Update Solve[N[Table[BernoulliB[n, z], {n, 10, 10}] == 0]] ...
1
vote
1answer
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: ...
0
votes
0answers
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 ...
3
votes
0answers
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 ...
3
votes
2answers
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: ...
4
votes
1answer
206 views

Compatibility issues for Combinatorica package

I am trying to use the Combinatorica package in a Mathematica version 9 in the following code : ...
1
vote
1answer
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: ...
4
votes
1answer
222 views

MapThread Alternatives

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 ...
3
votes
3answers
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 ...
10
votes
1answer
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 ...
1
vote
0answers
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 ...
2
votes
2answers
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 ...
5
votes
2answers
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 ...
5
votes
4answers
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 ...
0
votes
1answer
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 ...
1
vote
1answer
210 views

Function simplification: factoring $f(r,x)$ into $f1(r) \times f2(x)$ [closed]

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) ...
6
votes
3answers
322 views

Flow in pipeline graph

I have pipeline directed graph which has one source and several sinks ...
2
votes
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. ...
9
votes
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 ...
4
votes
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 ...
0
votes
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 ...
8
votes
2answers
261 views

Organise a graph's vertices into levels

I would like to organise a graph's vertices in levels. Consider ...
9
votes
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 ...
3
votes
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 ...
2
votes
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 ...
3
votes
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: ...
0
votes
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 ...
2
votes
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 ...
3
votes
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 ...
4
votes
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. ...
13
votes
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?
3
votes
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 ...
0
votes
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} ...
5
votes
1answer
70 views

Unequal and Compile

...
4
votes
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 ...
1
vote
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 ...
3
votes
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 ...
11
votes
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, ...
4
votes
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 ...
2
votes
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 ...
1
vote
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 ...
2
votes
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 ...
6
votes
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 ...
2
votes
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 ...
6
votes
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: ...
0
votes
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: ...
5
votes
0answers
122 views

The same analytical expression gets inconsistent FourierTransform results

I have an expression which is just a linear combination of plane waves, and I'd like to calculate FT of it. I know what I will get should be a bunch of delta functions, but it turns out Mathematica ...
6
votes
3answers
708 views

Customizing & finding intersection points in polar plot

I want to verify a theory stating that a golden mean spiral plotted on a polar graph will have intersection points at specific values. There should be 8 concentric circles, each at the same ...

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