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What does a/.b[c][] mean? [closed]

The function b[c_] has been previously defined. Does that "1" refer to the smallest number of a list?
41 views

A function for finding normal edge-5-colorings of cubic graphs

It would be nice if the following were available: Definition A normal edge-k-coloring of a cubic graph $G$ is a proper edge-$k$-coloring of the graph such that for any edge $e\in E(G)$, $e$ and the ...
35 views

RSolve gives negative solutions [on hold]

I'm getting some curious behaviour with a certain equation; I asked Mathematica to solve a recurrence relation, and to my surprise it actually could, as I was doubtful it had a closed solution ...
I am trying to learn if in Mathematica one can perform fits of analytic functions that are expanded and written as power series. In particular, we can consider the following generic form: $$f(B,x) = ... 0answers 44 views Prospective StartOfTime and EndOfTime in Mathematica When working with conditions for numbers we have a notion of \[Infinity] representing larger than any other number and similarly ... 1answer 26 views Derivative not evaluating when function defined I have the following code ... 1answer 37 views Three questions to customizing Ticks in Plot, LogPlot and LogLogPlot When making a plot, sometimes I would like to alter the ticks and labeling of the ticks, in particular when doing a LogPlot or ... 1answer 22 views Behavior of PlotLegends I want to have a plot of x^{\alpha}, where \alpha is an input, and a plot legend which displays something like \alpha = \# \text{ rad} on the following plot, where # is determined by the input. ... 0answers 42 views How can I handle box drawing characters? I must generate files for windows batch scripting, modifying template files, es. ... 0answers 33 views Print 4x4x4x4 tensor as 4x4 matrix of 4x4 matrices [on hold] I'd like to print the LeviCivitaTensor tensor as 4x4 block matrix of 4x4 matrices The following code works to display the LeviCivitaTensor tensor as a 3x1 vector of 3x3 matrices. ... 1answer 56 views Sum of powers of zero [duplicate] I would like to calculate the following sum Sum[0^(k-a), {k, 0, Nin}] for a positive integer a. With considering 0^0=1, my expected answer of the sum is 1, ... 2answers 64 views Save part of memoized function I have a function whose performing a series of expansions of a complicated function, which can take a lot of time. To avoid bottlenecks, I use memoization so I need to evaluate it only once. For ... 1answer 51 views How to generate such an image? Inspired by this, I'm using Graphicis to generate such a image, but it return I want every disk to be the same color. How to modify to make it work? Using image ... 1answer 34 views How to apply AlphabeticSort to a code cell? I've got a single code cell in a notebook with lots of Usage messages in no particular order. I'd like to alphabetize them, but doing it manually would be a ... 1answer 30 views How does Mathematica solve this 2D piecewise function from constraints? I am interested in learning the technique(s) used to solve the following 2D piecewise equation for x, y when given z, where z = f(x, y). \text{Given that x \in \mathbb{Z}, y \in \mathbb{Z}}... 1answer 29 views Problem with manipulate solution NDSolve and initial condition I'm getting crazy with this Manipulate : ... 2answers 30 views Piecewise function and deriving - solving I'm working in a (Economics) problem where I want to add two concave (profit) functions in order to maximize them together through one variable (quantity). My problem is that one of the two functions ... 1answer 31 views Interesting output in Integrate [closed] I found interesting behaviour, best illustrated in the following example. When trying to evaluate Integrate[1/(d^2 - 1), d] Mathematica 11.3 gives the following ... 1answer 35 views How to import a part of an Excel file? I'm trying to import a part of an excel, the column 20 and the row between 6-59 in this column. I tried : tab = Import[ "file.xlsx"]; time = tab[[20, 6 ;; 59]] ... 2answers 89 views Stability region of nonlinear ODE system Sol is the evaluation at t=100 of the solution of a nonlinear system of three differential equations with initial values at a, b, c. This is obtained with the function ParametricNDSolveValue. ... 3answers 403 views Numerical second order differentiation I have written a code for the second differentiation of numerical list ... 1answer 45 views In NCAlgebra, how can we make d**d**d=0 if d**d=0 is given? I wrote the following code to eliminate d^n from the equation for n>1. ... 1answer 154 views How to calculate \displaystyle \prod_{p}\frac{p^2+1}{p^2-1}? When I input$$ \prod _{p=2}^{\infty } \text{If}\left[\text{PrimeQ}[p],\frac{p^2+1}{p^2-1},1\right] $$in Mathematica 12.0, it gives out the value 1. The result is ridiculous, for that according to ... 1answer 31 views Comma separated images for .gif creation I recently created a key frame animation using Mandelbulber 2.18-1. Each .png image was placed in a folder with known location. I then dragged all the images and dropped them into a Mathematica ... 0answers 38 views Mathematica 11 in Ubuntu 18.04 does not display special characters in the notebook "Special" character, like pi (esc p esc), don't appear. They are instead replaced by a dotted gray square: How can I change this? Mathematica worked just fine before I upgraded Ubuntu to 18.04. I ... 1answer 44 views Turn PasteButton into keyboard shortcut I'm looking for a general "recipe" to do with a keyboard shortcut what I currently do with a PasteButton. Here is a working toy example ... 1answer 34 views Missing ticks and numbers on a plot when using JLink + Mathematica 11.3 I am facing a pretty random problem using JLink (Java) connected to a Mathematica 11.3 kernel and front-end. Basically I want to get an image using the JLink Java method ... 2answers 208 views Improving do loop speed with IntegerQ conditions The following program runs rather slow when the upper bound for n gets large (~6 secs for 10^5). ... 1answer 66 views Sharp jagged lines in Plot3D I have the following function of five parameters of which I would like to construct a 3D density plot using Plot3D ... 1answer 104 views Difficulty with numerically integrating highly-oscillatory function I'm interested in numerically solving a "highly-oscillatory" function. I've tried increasing the "max-recursion" and "precisiongoal", but it appears as though my answer is still not converging to the ... 1answer 57 views Inserting several lines in determined places of a 3D plot I have a special list instead of which I create another one by a Table ... 1answer 37 views How to make help open local help automatically instead of asking to choose each time? Since I am asking today about new changes in version 12 display, I might as well ask about this change. Each time, when asking for help using ?Command, I now find ... 0answers 94 views How to make version 12 print Root objects to screen normally as in earlier versions? From clean kernel, when typing result = Reduce[2 d^2 == -((2*(1 + d) + ((4 d^3)/(1 - d)))*(d - 1)),d] Here what version 12 displays on the screen, compared to ... 0answers 31 views Translate Mathematica Output to Latex type font [duplicate] In solving the inequality 2d^2\ge -(2(1+d)+\frac{4d^3}{1-d})(d-1), Mathematica returns something using Slots and Functions: ... 1answer 38 views How do I store the results of NDsolve, in a table for plotting later? Basically, I wanted to vary a parameter in my differential equations, while using NDsolve (ParametricNDsolve wasn't working for some reason, but that's for another question). I'm stuck looking for the ... 3answers 76 views Sum with variable terms to sum over Suppose I have a polynomial like this:$$a=x_{j_1} + x_{j_1}x_{j_2} + x_{j_1}x_{j_2}x_{j_3} + ...+x_{j_1}x_{j_2}x_{j_3}...x_{j_n}$$I want to create a function that takes this polynomial and does the ... 0answers 28 views FindEquationalProof to prove divisor theorem I'm trying to implement proofs of concepts for Equational Proofs on some basic number theory theorems. One such example is: "let a and b be positive integers and let d = gcd (a, b). If t divides ... 1answer 104 views Why doesn't Mathematica completely draw the fit? I have a question, and I really need your help, because I think I'm not understanding the reason... I have a potential model.. F[x_] := k x^n for the next ... 1answer 38 views Reduce all pairwise comparisons in a list I have a list of 37 values, like 2d^2 and 2d(1-d^2). I know I can use Reduce[] to solve an inequality of the values. For example, ... 0answers 34 views Using InitializePDECoefficients to solve a finite element problem I am trying to set up a differential equation using InitializePDECoefficients and then solve it using the finite element method. Below I show one calculation that ... 1answer 69 views Implicit Function Theorem I think I am stuck here right now: The exercise is to use implicit differentiation to determine y' considering the following equation: I managed to do this with: ... 0answers 15 views Strange Import behaviour from wls script I have a data file that is composed as follows ... 1answer 44 views How to write down a probabilistic function in Wolfram Language? How does one write a Wolfram function which has a 25% chance of returning 1, a 50% chance of returning 2, and a 25% chance of returning 3? Here is how the data structure might look like: ... 2answers 78 views Simplify w^{3n}, w^{6n}, w^{3 + 3n}, w^{4+3n}, etc. using w^3=1 I having an expression containing terms that are powers of w. How can I simplify these terms using the assumption w^3=1? ... 1answer 26 views Selecting only the terms whose exponents add up to a specific number Suppose I have the expression from a truncated series: ... 1answer 57 views Errors from NDSolve I'm trying to solve a system of PDEs with periodic boundary conditions using NDSolve. This works if I don't specify an initial condition (but is uninteresting, ... 4answers 235 views Threading data on TimeSeries Say I have two TimeSeries: x = TimeSeries[{2, 4, 1, 10}, {{1, 2, 4, 5}}] y = TimeSeries[{6, 2, 6, 3, 9}, {{1, 2, 3, 4, 5}}] x has a value at times: 1,2,4,5 y ... 1answer 43 views Simulation of bullet with cannon I want to reproduce a simulation involving a movable cannon and a movable target of varying size. The cannon is fixed such that the vertical height is variable but the x and y position is fixed. ... 1answer 27 views Replace series with restrictions I am trying to implement a code where I have the following problem: Consider I have the following series, which I can express as follows:$$ \sum_{j<k} x_j^4 x_k^4 = \frac{(\sum_j x_j^4)^2 - \...
A village has about 1 million residents. Suppose each resident has a jar with 100 coins in it.Two jars are considered to be “equivalent” if they have the same number of 10c, 20c, 50c, \$1 and \$2 ...