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

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0
votes
1answer
57 views

function of derivative of a function

I know a similar question is answered somewhere, but it doesn't work for my case for some reason. I have the following problem in Mathematica. I want to compute f[h[x]]= x^2 + D[h[x],x]. Here, h[x] ...
1
vote
1answer
71 views

Sort lists of vertices {indegrees, outdegrees} by indegree

in = VertexInDegree[F]; out = VertexOutDegree[F]; I want both in and out to be ordered by in. Example: graph has nodes a,b,c with indegrees 1,2,0 and outdegrees ...
0
votes
1answer
36 views

Defining arbitrary order derivatives function [duplicate]

I have a function $\phi(t)$ and I want to define a function $\phi D(t,r):=\phi^{(r)}(t)$, in other words evaluate the $r$'th derivative of $\phi$ at $t$. The naive code that I have is: ...
1
vote
1answer
46 views

Replicability of RandomVariate within a function?

I have a rather basic question but can't figure out a foolproof answer. In the following code, I build a function which returns the mean difference between successive elements of a vector created from ...
0
votes
0answers
29 views

Table of values for functions with random variables [duplicate]

I'm trying to get a table of values for functions with random variables. First of all, i have a function like that: ...
0
votes
1answer
71 views

Problems with For statement

I'm trying to iterate some expression through for loop: ...
0
votes
0answers
60 views

Financial Derivative european call option

When estimating financial derivatives like a european call option there is a parameter named: dividend paid per time unit. What does this mean, I have not been able to find any more information about ...
0
votes
1answer
87 views

Mapping a function over n levels

I want to map a function over a matrix of rank n, for example: ...
1
vote
3answers
122 views

Testing for continuity over a given domain

Is there any way to use Mathematica to test whether a function is continuous over a given domain?
0
votes
0answers
87 views

Solve function doesn't work

I have the following system of equations that I need to solve: ...
2
votes
0answers
96 views

A math function similar to “LatticeReduce” for finding linear independent basis

We would like to ask a math function similar to "LatticeReduce" for finding linear independent basis. The input is a list of vectors $M=\{v_1,v_2,v_3,\dots\}$, with the following property: There is a ...
1
vote
1answer
55 views

Compose two special power series expansions

I have two functions $A(x), B(x)$, given in a special power series form: $A(x)=1-x^{2}\left(\frac{a}{10}-\sum_{k=1}^{9}b_{k}\left(\frac{(x^{2}-1)}{r}\right)^{k}\right)$ ...
4
votes
4answers
202 views

Speed up replace all

I have large list of rules, I would like to use list/.rule, but assume that rule is a set of rules rule 1, rule2 rule...I want ...
1
vote
1answer
113 views

Time Varying Payoffs?

I'm trying to write some code that will return the final value of an annuity whose monthly payouts may or may not be constant each month. Right now I have working code for constant payments, but I'm ...
1
vote
1answer
170 views

ListDensityPlot

In Mathematica help it's written that: ListDensityPlot[array] -> generates a smooth density plot from an array of values. ...
6
votes
1answer
111 views

Is it possible to circumvent a bug inside SeriesCoefficient?

As far as I can tell, there seems to be a bug in SeriesCoefficient: ...
1
vote
1answer
113 views

How to define a list that contains all primes less than x?

how can I define my own list in which I have all primes less than x?
0
votes
3answers
76 views

Half kth term if n is even and k=n/2?

I am trying to write a function which will perform the equation in the attached image. So far, I have: ...
2
votes
1answer
119 views

Matrix exponential MatrixExp[] vs Sum[MatrixPower[]] doesn't match?

I might be an idiot, but I cannot get the manual expansion of e^At to match the MatrixExp[A t] result. For example, I have the following: ...
2
votes
1answer
122 views

Discontinue, then continue x-axis of 2D Histogram

I have the pictured Histogram. It was generated by the following lines: ...
0
votes
2answers
208 views

How to find number of connected components of graph G?

Is there a command that can count the number of components of a graph, in the same way that VertexCount[G] counts vertices?
0
votes
0answers
41 views

Time varying Poisson rate using ParameterMixtureDistribution

I have a system in which there is a Poisson arrival process with rate $\lambda$. I need to split this process into two independent poisson processes $\lambda_i$ and $\lambda_u$. Where ...
0
votes
0answers
16 views

Using functions as input for a function - won't simplify [duplicate]

I've defined a function P[k_] := 1/[Sqrt]2 (R[k] + L[k]) where R and L generate matrices. However the output of this function never full simplifies (even when I use the Simplify[%] functions). It ...
1
vote
0answers
120 views

Derivative of the Absolute Value Function in Mathematica looks very different from the actual answer

Derivative of the Abs Function in Mathematica looks very different than the actual answer. Why? How to correct this? For example I entered ...
31
votes
2answers
919 views

Variable naming changes everything

I am having a rather unusual problem I do not understand with Mathematica where renaming one of the variables of my function causes the function to stop "working". Here is the example of the code ...
1
vote
1answer
73 views

FlipView Alignment problem

Here's the problem with MWE: Framed[ FlipView[Framed /@ {100, 1}, Alignment -> Center] , ImageSize -> {100, 150}, Alignment -> Center] I ...
2
votes
1answer
140 views

A question about definite integrals and timing

I need to integrate the expression G given below: ...
0
votes
0answers
43 views

Plot two functions of two variables against each other [duplicate]

I have two functions f1(n,m) and f2(n,m) but the issue is that f1 generates many values say ...
0
votes
1answer
76 views

Blank plot that shows up briefly when changing plot options

I wrote some code in Mathematica to calculate and plot, in tw0 different ways, a function depending of two variables. But the plots are empty even if it takes a few minutes to evaluate the plot ...
2
votes
0answers
63 views

Complicated output from simple Eigenvalues problem

I have code that uses Eigenvalues on matrices of various sizes. But the output of what should be a very simple problem, namely finding the eigenvalue of a 1x1 matrix, is overly complicated. ...
3
votes
2answers
315 views

Manipulating slots in a pure function

How does one manipulate the slot numbers in a pure function? Some trick with Evaluate or Hold? I'm aiming for something along ...
0
votes
0answers
42 views

Verify “Type” of solution [duplicate]

I've written some Mathematica functions which allow the user to verify if a mathematical function has certain properties. What I'm basically doing is generating "random" functions in respect of ...
3
votes
2answers
218 views

How to copy a function by value?

I need to change a function symbol multiple times by assigning another symbol to it, but when I'm trying to do that the symbols overwrite each other. I'm assuming this is because the assignment is by ...
0
votes
1answer
58 views

nested series expansion

I have to invert the following matrix in which the functions U[t,x,y,r] and K[t,x,y,r] and all their derivatives are "small"; ...
1
vote
1answer
72 views

Selection of the position of the variable

I defined a function funloglogplot to make a loglogplot of a function (function1) depending on several variables ...
1
vote
0answers
23 views

Minimizing roots of a transcendental equations [duplicate]

I'm trying to use the solution of FindRoot with parameters for further calculations. Annoyingly enough it always gives me trouble with replacing the parameters. As an example I'm attaching a simple ...
0
votes
2answers
176 views

How to find intervals in the domain corresponding to intervals in the range?

I want to find the intervals for the argument m1 of this function corresponding to the value for the function lying in given intervals of the range: ...
1
vote
0answers
38 views

How can I use the Rules returned by FindFit? [closed]

When I evlauate data = RandomReal[10, {5, 10, 2}]; fit[i_] := FindFit[data[[i]], a Sin[x] + b, {a, b}, x] fit[1] I get something like: ...
0
votes
0answers
51 views

Fold Dynamic Function [duplicate]

I'm making on a demo working with differential equations as functions of two variables (x and y). The demo will have to Fold the differential equation with an initial y-value and a series of x-values. ...
0
votes
0answers
130 views

Calculating the Lyapunov Exponent/Spectrum for the Duffing Oscillator

Some fellow students and I are trying to calculate and plot the Lyapunov spectrum for the Duffing oscillator (currently a test approach). Each of us has Mathematica knowledge based purely on past ...
0
votes
1answer
106 views

A problem with set values

The following code is just an example to clearly explain my problem. Assume that : ...
0
votes
0answers
102 views

A problem with functions and Infinite expression 1/0 encountering

Following code (function) makes integrals and then replace f[x] with Cos functions and calculate the definite parametric ...
1
vote
2answers
187 views

How to apply function f for each time value t, to each pixel from image, resulting in t images

I have a 2D array of complex values and I want to apply a function to every entry of the array, for every timepoint t in a list. I know how to apply my function to one entry for every time t in a ...
3
votes
2answers
138 views

Need to create a function to generate all permutations of Range[$n$] [duplicate]

Basically I need a function that takes a list and gives all the possible permutations of it. The reason I can't use Permutations is that I have to apply another ...
1
vote
1answer
93 views

What is happening in Map[Function[x, x^2], a + b + c] from the Pure Function tutorial

The Pure Function tutorial gives an example: Map[Function[x, x^2], a + b + c]. I would expect the output to be (a + b + c)^2, ...
4
votes
2answers
247 views

Understanding Transpose

It is very likely that it is my lack of math skills that is showing up here. However, I think Transpose is such an important function that I need to master it. So I ...
2
votes
0answers
53 views

Can BreadthFirstScan be modified?

I would like to obtain a "slick" implementation of A*-search algorithm on Graph objects, using the built-in BreadthFirstScan (if that is possible at all). I noticed that BreadthFirstScan is static in ...
2
votes
1answer
105 views

Dynamically Updating Function

I use Mathematica 8 and am working with DynamicModule. I'm trying to enter a function in an InputField then later apply it to two values entered in subsequent Input Fields. The function just does not ...
1
vote
1answer
91 views

Problem with System`Graph and Combinatorica`Graph functionality conflict

I'm trying to generate a random geometric graph. When evaluating HighlightGraph, even if I am passing graph object Mathematica always gives error like A graph ...
14
votes
1answer
312 views

How to represent a continuous monotonic phase of Airy functions?

Note: In this question I am concerned only with real-valued variables and functions. DLMF, §9.8 Airy Functions, Modulus and Phase, formula $9.8.4$ defines the phase of Airy functions: ...