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Plot a sum of vectors using inline free format or wolframalpha. What is the hidden code?

Using Wolframalpha or inline free format you can obtain a nice representation of a sum of vectors. An example is shown below. Whish is the hidden code? (or a code that make the same representation). ...
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0answers
3 views

Nonlinear Difference Equations

How can I plot the nonlinear difference equations? I try to use the continuous code but I do not know if its work with difference StreamPlot[{x+ .01 (0.4(x^3) - .2 (y^2)x + 1.1 (y^3) y+.01(-9x^3+9xy^...
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0answers
7 views

Export styled grid to latex

I'd like to write a ExportString for Grid and/or TextGrid with basic style elements into Latex tables. I would it at least ...
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2answers
14 views

expansion of hypergeometric series

I am completely new to mathematica. I am not sure how to calculate the expression 2F1. Is it possible to a closed form solution in terms of z of the hypergeometric series 2F1(-a, N/2-a, N/2; z) and ...
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0answers
13 views

Easiest way to export amplitude from FeynArts to FeynCalc

I am having trouble calculating some unpolarized squared amplitudes with FeynArts+FormCalc and want to use FeynCalc to manually handle the amplitudes calculated by FeynArts. What is the easiest way to ...
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0answers
18 views

NonLinear system for chemotaxis

I want to solve the chemotaxis mode, given by the next non-linear system: It is taken from Murray's book: equation (11.30) at pag. 408 $$\frac{\partial n}{\partial t} = D \frac{\partial^2 n}{\partial ...
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2answers
27 views

Stacking Multiple Graphs together in seperate plots

I have been working on a problem where I wanted to stack multiple graphs on top of each other in the following format I tried to look for solutions to do the same but I could not. The closest I could ...
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0answers
19 views

How do I find how many numbers are prime(taking absolute value of negatives) in a list? When i use count it returns zero

f = 9x^2 - 78x-10000 list1 = PrimeQ[Abs[f /. x -> {Range[1, 20]}]] Count[list1,True] This is my code. Im trying to find how many prime numbers ...
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0answers
17 views

Suggestion for parallel computation

I have a casual question about tips and tricks for parallel computation in Wolfram. As far as I know, Wolfram doesn't exploit both your CPU cores and you need to code for parallelization. How does it ...
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1answer
15 views

How to plot the solution region of system of inequalities with slack variables?

There are already related questions to this one, but I could not transfer these solutions to my problem. I have the system $\sqrt{t_1^2+u_1^2}+\sqrt{t_2^2+u_2^2}\leq 1$, $x=2t_1-u_1+2t_2+u_2$, $y=...
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0answers
11 views

Apply Formula automatically in Feyncalc

I want to apply the function Tdec in Feyncalc automatically. Here is an example what the input is: ...
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0answers
17 views

Conditional Summation involving factorials

I am trying to input $$g_m=\sum_{m=l_1+l_2+...+l_r\\p_i~distinct~odd~primes\\such~that~p_i|l_i}\frac{1}{\Big(\frac{l_1}{p_1}\Big)!...\Big(\frac{l_r}{p_r}\Big)!}$$ Now here factorials are involved and ...
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0answers
23 views

Steady state customer behavior in queuing model — Numerical Optimization

With the following code I try to calculate the steady-state equilibrium waiting time at two different queues. A fraction tau of users turns away entriely, a ...
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0answers
21 views

Alternative for underscore delimiter

If I want to have a variable name that contains multiple numbers but where it is important that the numbers be separated I would usually use underscores (as in C, e.g. p_3_23), dashes or dots (for ...
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0answers
46 views

Fitting a two-dimensional Gaussian to the image

I have a image which I want to fit 2d Gaussian function with that. I used the below codes but the output figure doesn't look alright. I extracted the mean and covariance values in x and y direction.I ...
0
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1answer
30 views

My rule does not do anything (understandably)

I want a rule that would transform, for example, And[i,F[j,k],l,G[m,F[j,k],n],p] into And[i,F[j,k],l,G[m,T,n],p], where ...
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1answer
18 views

Solve a ODE with specific conditions

I am trying to find (some) functions h(x,t) such that A h(b,t)+B h_x(b,t)=g(t), where A,B,b are constants and g(t) is a given function of time (h_x is the partial derivative w.r.t. the first component ...
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0answers
33 views

Displaying many ROC-curves

I did a classification using Classify. I sampled 20 times. To calculate the mean accuracy, etc., is easy. But is there also a way to overlay the calculated ROC ...
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0answers
25 views

Passing python data types as function arguments

I've a few python data types ...
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1answer
46 views

Newton's divided differences iteration

I am trying to write a program that forms the interpolation polynomial for a given function on a given interval for any number of data points n. I wish to write a formula that will compute all of the ...
5
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2answers
98 views

Counting Elements in Multiple Lists

How to build a table that counts how many times each element in mainlist occurs in lst1, lst2, lst3, lst4 and which lst1, lst2, lst3, lst4 contains that element. For example, in mainlist, element ...
0
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1answer
13 views

Multiplication of certain terms in a sum within a vector

Is there any way to multiply certain terms within a vector with a constant? e.g. assume that I start with a vector {f[4] - g[-1] , h[2] , 2 * g[2] + h[-1]} where f[ i ], g[ i ], h[ i ] are functions ...
2
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1answer
27 views

Trying to create a list that counts the number primes for each remainder class

Considier the remainder of the first $2500$ prime numbers by the numbers from $3$ to $30$, included. Calculate how many primes are in each remainder class. That is, create a list that for each number ...
2
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2answers
63 views

How to draw tilted axes for spacetime diagrams

I want to use Mathematica to draw spacetime diagrams. In particular, on one of these diagram, I'd like to draw two pairs of axes. The first pair $(t,\,x)$ for the rest frame and the second pair $(t',\...
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0answers
36 views

Evaluate 3D- and 5D-constrained integrals for absolute separability probabilities

In a recent posting, TwoQubits user JimB, employing a change-of-transformations put forth by N. Tessore, was able to confirm a formula for the "two-qubit absolute separability Hilbert-Schmidt ...
7
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3answers
168 views

What is a good way of perfoming operations on specified columns of a table with many columns

If I have a table of data and I want to do a specific operation on say the third column, I usually do something like this: ...
1
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0answers
28 views

Segmenting a binary image into three parts

I am trying to segment a binary image into three parts, head, body, and tail. The binary image is a stack of tiff files of a moving fruit fly larvae. I was able to do this initially by removing points ...
4
votes
3answers
228 views

How do I get a list of all possible sums in a list nested list?

Lets say I have the following input: rn={ {1, 1.1, 1.5}, {5, 6, 6.1, 7}, {8, 8, 12, 12, 12.5, 13} } This input has the dimensions of ...
1
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0answers
20 views

Simplify Equation with variable unequal to zero

How can I simplify the following equation with Mathematica assuming z!=0? I have the following code: ...
0
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1answer
19 views

GeoRegionValuePlot Leaving Out Metropolitan Census Tracts

Preamble Run this code in the preamble for a working example of what I'm dealing with. Census Tract Entity Store ...
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0answers
23 views

Finding the maxima and shading the region from $x=0$ to the $x=max$

I have the following code: ...
2
votes
3answers
63 views

Trying to get text in square to transform together

I use Graphics[{EdgeForm[Thick], LightGray, Rectangle[], {Black, Text[Style[F, FontSize -> 442, Bold, FontFamily -> Arial], {1/2, 1/2}]}}] to put an "...
0
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1answer
35 views

Plot of asymmetric curve with vectors

I am trying to find a sloution for the following application. I have a centre of gravity (CG) and want to revolve a tube (telescope) around it. CG is 480mm from the vertex that corresponds to a ...
1
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0answers
32 views

RegionIntersection not work, only outputs BooleanRegion Object

This is an example to make Pi in 3D dimension Thanks @xzczd for providing the fast version. Link Smoothing the Region? ...
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0answers
19 views

For any countable well-ordered $A$, how can mathematica show my choice function gives a unique collection of finite sets whose union is $A$?

Suppose $A=\sqrt{\mathbb{Q}}_{>0}$. We want a unique $\bigcup\limits_{i\le j}A_i$ for $i,j\in\mathbb{N}$ such that $A_i$ is finite, $A_i\subseteq A_{i+1}$, and $\lim\limits_{j\to\infty}\bigcup\...
2
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2answers
59 views

How can I plot Sinc function and avoid their auto-replicas?

The problem is to plot the 3D Sinc function, but I cannot avoid the self-projection. I use the following code: ...
1
vote
1answer
47 views

How to write Ordered partition in a summation involving a huge expression

$$b_n=\sum_{m=2}^{\lfloor\frac{n}{3}\rfloor}\left\{(-1)^m\frac{l_m}{m+1}\sum_{i_1+i_2+...+i_m=n}a^{(1)}_{i_1}a^{(2)}_{i_2}...a^{(m)}_{i_m}\right\}$$ The $i_k\geq3$, for any $k$. Here $a^{(k)}$ ...
0
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1answer
69 views

From a bag of n balls, with c colours, and d draws count how many variations are possible?

First, the objective is not to use formulas for combinations, or permutations. The objective is to use loops(for, while, etc.) to make Mathematica count the number of possible variations/sequences of ...
1
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0answers
39 views

How to simplify this output with ArcTan[Tan XXXX ] [closed]

Integrate[Tan[3 x]^2, x] Why couldn't it simplify the answer to -x + 1/3 Tan[3x] so to speak
1
vote
1answer
27 views

ColorFunction issues. Using different colors for different values of x

I am attempting to generate a plot for which the color changes for selected values of x as determined by a function. Below, is my best, unsuccessful attempt. The specific problem with this is that it ...
0
votes
2answers
36 views

How do I construct a matrix using table command. I can not form it's function

I have to form a matrix like this. How ever I can not directly input. I have to form a function and then use the table command. I am stuck. {{2,5,10},{9,12,17},{28,31,36}}
0
votes
1answer
48 views

How can I plot 3-D system

If I have three equations nonlinear. I need to see the behavior around (0,0). How do I plot the three-dimensional system? Thank you in advance. I try to use this code ...
1
vote
1answer
57 views

Creating a list that shows the numerical values not in boolean form

Based from the equation I used in the code below, I found how many values are divisible by 5. However, this is in boolean form. I only know how many are divisible by 5 which is 7500. I need to ...
1
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2answers
39 views

Concatenate matrices in a specific way

Is there an elegant way to start with a matrix of the form $$ A = (B,C) $$ where B and C have dimensions n x m, and construct a large matrix that looks like $$ \begin{pmatrix} B & C & \mathbf{...
2
votes
1answer
38 views

A doubt on ParametricPlot3D, RevolutionPlot3D, ListPlots and NIntegrate: can I build an “RevolutionListPlot3D”?

First of all: this is question lies in the context of Surfaces and Embbedings on differential geometry. More precisely in the context of Kruskal coordinates and how to plot a 3D dynamical ...
0
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1answer
43 views

Turn vector equation into matrix multiplication

I have physical equations of motion that describe the dependence of one vector field on the components of another vector field. Without getting too much into detail, my differential equations involve ...
6
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3answers
133 views

To hatch bar in BarChart

I have this code: ...
0
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1answer
62 views

What does the {-y,x} in this equation mean? [closed]

What does the {-y,x} in this equation mean? .5 {-y,x}/(x^2+y^2)
2
votes
1answer
33 views

How do you ask someone to input the values of a matrix?

I'm trying to set up code that basically asks the user to input the values of a matrix with a certain key size. I want them to first enter the keysize and then ask for all of the entries necessary to ...
1
vote
1answer
36 views

How can I apply code that calculates one element of a list to the whole list?

I have a problem with a while loop in Mathematica. I want to run the whole list "mFromAlice" in the while loop but I dont know how to do that. It works with the first row, which is named x ...

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