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

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0
votes
0answers
29 views

Horizontally compress a picture with varying compression ratio

I have a function c[x] whose domain and range are both [0,1]. And I have a picture with width W, height ...
2
votes
3answers
191 views

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

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 ...
0
votes
2answers
47 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 ...
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
200 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 ...
10
votes
6answers
661 views

Will Version 9 functions all work in Version 10?

Having developed a substantial code base in Mathematica 9, leads me to ask these important questions prior to downloading and installing Mathematica 10. Will any Mathematica functions from the ...
20
votes
2answers
426 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 ...
5
votes
3answers
185 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) ...
1
vote
1answer
143 views

How to apply a tensor to a list of arguments

The problem I have is the following: Let C be a list of coordinates, say, C = {x1, x2, ..., xn} and ...
6
votes
1answer
89 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 ...
2
votes
1answer
105 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
2answers
304 views

How to plot several functions without jumping? (multiple eigenvalues of a system as functions of 2 parameters)

I've been working on this research problem for months with some success by no global/proper solution to the problem. So I have square, Hermitian matrices of various sizes ($8,20,38$ dimensions) with ...
0
votes
2answers
78 views

Collapsing summation

I am trying to write a command to collapse the sum of terms into an expression with summation. Something like ...
1
vote
2answers
68 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 ...
3
votes
5answers
231 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
2answers
216 views

$RecursionLimit::reclim: Recursion problem

Please, find bellow my original question. Here is all my code: ...
0
votes
0answers
24 views

Use WeatherData from many location [closed]

Can anyone tell how can I predict the weather data in my location using weather data in other locations? Sort of algorithm, or equations??
2
votes
1answer
83 views

Define PolyLog so that positive reals evaluate on upper edge of branch cut

Generalizing the previous question: Define Log so that negative reals evaluate on lower edge of branch For real positive values $x>1$, Mathematica's polylogarithm function ...
14
votes
5answers
5k views

How to find the domain and range of a function with Mathematica?

I'm studying calculus and in some exercises I am asked to find the domain and range of a function. Does Mathematica have already a built-in function for this? I can imagine some ways of doing so, ...
-3
votes
0answers
67 views

Get the function of a scatter plot [closed]

Considering we have a scatter plot and the best linear fit of the data, and also average error of it, how can we get the function from that plot? The plot is I get it with ...
2
votes
1answer
165 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 ...
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
39 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
172 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
57 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
92 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
votes
1answer
68 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 ...
1
vote
1answer
53 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 ...
3
votes
0answers
63 views
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
39 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 ...
7
votes
3answers
281 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? ...
18
votes
4answers
594 views

Accessing list elements by name

First, a bit of a long introduction to my problem: I only have a few weeks of Mathematica experience. I am creating a mathematica application that calculates some material properties of steel based ...
5
votes
1answer
70 views
2
votes
1answer
172 views

Plotting attributes of vertices in WattsStrogatzGraphDistribution[n, p, k]

I have a graph WS = RandomGraph[WattsStrogatzGraphDistribution[n, p, k]]. I need to plot several characteristics of each v: the ...
3
votes
1answer
161 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 ...
3
votes
0answers
114 views

What is the difference between Block and Module? [duplicate]

Possible Duplicate: What are the use cases for different scoping constructs? I don't understand the difference between the Matheamtica functions Block ...
4
votes
4answers
250 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 ...
2
votes
3answers
79 views

Problem with InverseFunction of Sqrt

I want to build a table of InverseFunctions, f.e.: ...
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
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: ...
4
votes
3answers
196 views
0
votes
1answer
28 views
1
vote
1answer
101 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 ...