Questions about the use of built-in Mathematica functions, including pure functions.

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0answers
16 views
0
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0answers
69 views

Simulation of Circular plate vibrations

I'm trying to simulate the vibration of a circular plate with a free edge. The plate wave equation describes the vertical displacement of the middle surface of the plate $(\zeta)$ as a function of ...
0
votes
0answers
74 views

plot $f(x)$ against $\frac{1}{x}$ [on hold]

Hi guys this is really a simple question: if i have $f(x)$ how do i plot this function in mathematica against, for example, $\frac{1}{x}$? thanks in advance
7
votes
5answers
298 views

What is my problem with MeshFunction?

I want plot the max value in a sine plot. We can use the following code ...
0
votes
0answers
40 views

Simplifying Products In Mathematica [on hold]

I have, amoungst many others, the function: Kbox[n_, r_] = ((n - r)*r)!/ Product[Product[(r - i + 1) + (n - r - j + 1) - 1, {i, 1, r}], {j, 1, n - r}] ...
4
votes
4answers
208 views

implement the ZOH in mathematica [on hold]

well I'm trying to implement the ZOH in Mathematica, but I can't. Take a look, this is my script: ...
1
vote
1answer
87 views

Horizontally compress a picture with varying compression ratio [on hold]

I have a function c[x] whose domain and range are both [0,1]. And I have a picture with width W, height ...
1
vote
2answers
54 views

How to use the output we see of expression when this expression is inside Dynamic

Consider this example: Manipulate[status = Dynamic[If[a < b, Yes, No]], {a, 2}, {b, 5}] The output of this calculation is ...
2
votes
3answers
204 views

How can I get the function of a plotted trajectory? [closed]

I solved two ODEs, which are a function of t, numerically. The first ODE is the vertical equation of motion and the second one is the horizontal equation of that ...
1
vote
1answer
73 views

Attaching functions to movable locators

I'm trying to create a manipulate plot showing the electric field due to a collection of point charges. At the moment I've created such a plot which allows the x and y positions of each charge to be ...
10
votes
2answers
205 views

Why isn't Lookup treated like other symbols?

With Mathematica 10, I wanted to overload Lookup using TagSetDelayed, but it doesn't work. For instance, if I define two objects ...
5
votes
3answers
214 views

Solving $L=\frac{3}{2} \sqrt{4 \pi ^2 A^2+W^2}-\frac{\sqrt{5 W \sqrt{4 \pi ^2 A^2+W^2}+6 \pi ^2 A^2+3 W^2}}{\sqrt{2}}+\frac{3 W}{2}$ for $W$

When I solve the aforementioned equation for $W$ or $A$ on Mathematica I get a long and ugly equation in return, namely one of the solutions for $W$ is: (attempt to read at your own health) ...
6
votes
1answer
92 views

How to sort the functions in a Package?

Once a Package like abc` has been installed, we can use "?abc`*" to scan all the functions defined in this Package. Now I ...
1
vote
2answers
69 views

How to define logical expressions for platonic solids?

A more general question would be: How to find logical expressions for 3D-objects described by closed polygon sets? Finally a simple question is more prolific, therefore: How to define logical ...
2
votes
1answer
109 views

RegionPlot3D run forever when plotting 3D ParametricRegion

when working with 2D, RegionPlot works fine with ParametricRegion as can be seen in this example: ...
3
votes
5answers
236 views

How to add periodicity to condition?

Is it possible to set the following function f[a], where a can be any real number? $$ f(\alpha) = \begin{cases} 1 ...
0
votes
0answers
24 views

How to prevent function from substituting the part of the parameter name if it has a subscript? [duplicate]

I have the following problem, when defining and using a function, that's supposed to have an outside parameter xmin: A[x_] := Exp[-x/Subscript[x, min]] A[5] ...
2
votes
1answer
166 views

Finding average error of the data

Considering I have some data, and I want to fit the data to a linear fit and find the average error from the linear fit, how can I do that using Mathematica? I have ...
-2
votes
1answer
40 views

Compile Determinant [closed]

I would like to determine the determinant of a 4x4 matrix with the entries a[i,j] being functions of $i$ and $j$. I used Compile with code: ...
5
votes
1answer
175 views

How can I make a “self-referential” replacement operation self-contained?

Fairly often I find use for replacement rules that call themselves on the right-hand side of the rule, e.g.: ...
1
vote
0answers
59 views

How do I choose only one branch of ArcTan?

I have a problem concerning ArcTan drawing a graph using ListPlot. I import a table of data: ...
2
votes
0answers
31 views

Evaluating standard functions of general quaternions symbolically

Mathematica can easily compute exponentials and logarithms of concrete quaternions: ...
2
votes
1answer
94 views

How to explain the behavior of Rule inside these functions [duplicate]

I'm trying to define a function that takes an expression and spits out a pure function involving a replacement rule of that function's variable. An example would be a function ...
0
votes
0answers
24 views

Use FindRoot solution as number in function [duplicate]

I would like to save a number that I gain with FindRoot so that I can use it in another function. I tried: ...
0
votes
0answers
9 views

on characterization of a riesz homomorphism on C(X) spase [migrated]

what is proof that:Let K be an arbitrary topological space and π : C(K) −→ R be a map with π(1) = 1. if π is a algebra homomorphism then it is an Riesz homomorphism.
1
vote
1answer
54 views

Remove curly brackets _completely_ to map a function to the elements of a list [duplicate]

Most list manipulations can be done with Flatten, Partition and Take. I didn't managed to ...
4
votes
1answer
97 views

Measuring time complexity of a method

I use ...
-1
votes
1answer
70 views

Find minimum function value in data and give coordinates of minimum

I create with Table an array containing the function value of some function and the n1and ...
0
votes
0answers
13 views

how to get Gamma function in Mathematica using Matlab [migrated]

In Mathematica, Gamma[a, z] refers to the upper incomplete Gamma function whereas in MATLAB, gammainc(z, a) refers to the regularized lower incomplete Gamma function. I want to know how can obtain the ...
1
vote
1answer
115 views

Finding the minimum of a function

I asked this question Mark Minimum Value in DensityPlot. Another question has come up, or better said, a task: Find the minimum of a function. I haven't been able to write the needed code for that, ...
0
votes
0answers
12 views

For nonempty sets A and B and functions f: A-> B and g: B-> A, suppose that g of f = i_A. Prove that if f is onto, then g is one-to-one [migrated]

Here is what I started, I don't think it's correct. Suppose f is onto, so then there exists an element b in B s.t. for all a that is an element of A, f(a)=b. (definition of onto). Let y,z be any ...
2
votes
1answer
56 views

How to create a numerically “equal” function?

A simple example about what I need to do. For example, I have three functions: t1[x,t] t2[x,t] t3[x,t] and, ...
2
votes
0answers
40 views

Maximizing Large Multivariable Function over Region with Parameter Constraints

Brand new Mathematica user here. I have a complicated function to maximize, and thought I would try software like Mathematica instead of taking derivatives by hand. I found some Mathematica ...
0
votes
2answers
216 views

$RecursionLimit::reclim: Recursion problem

Please, find bellow my original question. Here is all my code: ...
6
votes
3answers
284 views

Does Mathematica have Month Range and Day range?

It is known that CharacterRange["a", "z"] gives list of characters from a to z. Does Mathematica have something similar for weekdays and months of the year? ...
0
votes
1answer
56 views

Problem with Maximize

As $\{p1,p2,p3,p4,p5\}$ represents a probability distribution and $l1,l2$ are the eigenvalues of a stochastic matrix, the function $f$, as defined below, has to be maximized over a certain region. ...
2
votes
3answers
79 views

Problem with InverseFunction of Sqrt

I want to build a table of InverseFunctions, f.e.: ...
4
votes
3answers
196 views

Is it possible to specify which range that slot takes from?

consider this example: ...
3
votes
1answer
174 views

Circular membrane vibration simulation

I'm new in Mathematica and I'm trying to simulate the vibration of a circular membrane for math project but I don't even know how to start. The wave equation describes the displacement of the ...
4
votes
4answers
251 views

How can I get the number of slots in Function?

Suppose that I define f = Function[#1 + #2]; And I want to define a new function, argsNum, so that it returns a number of ...
0
votes
1answer
28 views

Why would this function work only when I make a copy of the variable? [duplicate]

Why would this function work with a copy of the function variable: ...
20
votes
2answers
431 views

Why is Query so much slower than Part?

Time for another of these(1),(2) as yet another new-in-10 function appears to have poor performance compared to older alternatives. This time: Query appears to be ...
2
votes
1answer
79 views

How to generate specific function using BSpline command/

I want to generate an approximation function that fits a curve to points. My goal is to obtain an actual formula. Is this possible with the BSpline function? Using the following code: ...
1
vote
1answer
102 views

Solving a trigonometric equation with one parameter

I have the following equation: 2 a^2 k^2 Sin[b k] - 6 a (k Cos[b k] - Sin[b k]/b) == 0 I set the value of b to 1, and I want ...
10
votes
5answers
290 views

How to prevent function from passing values to slot

For the following example: {#, #} & /@ {1, 2} I am trying to find a method to hold one of the slots (or both ) so that the function do not pass the values to ...
4
votes
1answer
198 views

Use of Strassen's algorithm

Strassen's algorithm is an algorithm for matrix multiplication that is asymptotically faster than the naive one. In practice, the matrices involved have to be quite large before Strassen's algorithm ...
2
votes
1answer
74 views

How to determine Fixed Point of a function? [closed]

A function is defined as f[x_]=Sqrt[1-x^2]. How can I determine the fixed point of f? I've tried this: ...
-2
votes
4answers
165 views

Compare elements in a list

Assume that there are three different points in x-y coordinate like: p1={4, -1}; p2={5, -2}; p3={1, 5}; In order to compare these points to each other in a ...
0
votes
0answers
30 views

How can Mathematica solve 7 equations and want to find 7 variables [duplicate]

I have 7 equations as below * e1 := (1 - a) p Subscript[A, 0] Subscript[s, K ] ! *SubsuperscriptBox[(s), (L), (-a)] = (1 - b) Subscript[B, 0] (1 - Subscript[s, K]) (1 - Subscript[s, ...
0
votes
2answers
73 views

prime-palindromic number selected from a list

I want to find all prime-palindromic numbers up to 5000. Prime-palindromic numbers are numbers that themselves and their reverse digits are both primes. For example, 31 is a prime-palindromic number ...