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

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1
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1answer
102 views

Evaluate pure function through round brackets

In have some matrices of pure functions or numbers which I multiply by other matrices or vectors. I would like the functions to be evaluated in the result, but all that I get is something like this: ...
4
votes
1answer
95 views

Evaluating standard functions of general quaternions symbolically

Mathematica can easily compute exponentials and logarithms of concrete quaternions: ...
0
votes
0answers
26 views

PolynomialExtendedGCD in 2 variables

Consider a field $R$ and the ring $A=R[y]$. Consider two polynomials $g,h\in A[x]$. I want to obtain $d=\gcd(g,h)\in A[x]$ and two polynomials $s,t\in A[x]$ satisfying the Bézout relation: $sg+th=d$. ...
7
votes
0answers
54 views

Is it better to completely forget about the existence of PowersRepresentations?

I noticed that in several cases the performance of PowersRepresentations is hugely worse than that of IntegerPartitions. (Mma ...
3
votes
0answers
65 views

Accuracy of PrimeQ function

Using PrimeQ in Mathematica 10 on integers up to $2\cdot 10^{5717}$ the function appears to work. The Documentation for Mathematica 5 says that ...
4
votes
0answers
103 views
0
votes
0answers
25 views

Is there a way to save the output from integrate as a function? [closed]

Is there a way I can save the result of my integration as a function? I would like to be able to assign the result of this integration to a function which accepts ...
2
votes
2answers
57 views

Substituting within a function definition that includes Simplify

I would like to define a function like myfunc[f_] := Simplify[(f/g)] where g will be substituted/replaced with the current value of g at the time of definition. ...
3
votes
1answer
66 views

Checking if input is a function

I would like to write a program to find the leading coefficient of a given polynomial. (Sounds easy, right?) I'd like to be able to handle the format x^2-x+7 (with ...
3
votes
3answers
171 views

Return a sentence with numerical values

I have the following function: example[a_, b_] := Module[{c}, c = a + b; Return["The solution is c"] ] I would like to know how to return that ...
3
votes
1answer
44 views

What function superseded SpaceForm?

In older versions of Mathematica you could use SpaceForm to leave a certain amount of spaces when writing to a file. For example, if we have the following data: ...
10
votes
1answer
167 views
0
votes
1answer
53 views

Transform a variable's exponent from an exact rational to an inexact decimal

here is a little problem I could not find a solution for. I have a variable with an exponent represented as a fraction, for example, var = a^(39/106) Now I ...
0
votes
1answer
131 views

Check an inequality if one condition holds

A = Abs[-1 + 1/(1 + β)] + Abs[-((1 + 2 α + Sqrt[1 + 4 α + 4 α β])/(2 α + 2 α β))] Is A <1 if ...
6
votes
2answers
306 views

What does empty {} mean in Module? [duplicate]

I have a question. I would like to know what an empty list ({}) means when used in Module[] as the code below shows? Why has a ...
16
votes
1answer
360 views

GeoGraphics: problem with GeoPosition in shifted projections

Bug introduced in 10.0.0 and persisting through 10.4.1 A remark about the answer: My work around is only nice for simple cases with points. More general should include proper polygons splitting on ...
1
vote
2answers
89 views

n fold convolution of a function via a recursion function

I wanted to write a recursion function to calculate the n-th convolution of a function f[x_]. I wrote the function ...
0
votes
1answer
52 views

Partial derivative of function of two variables

This question is not enlightening nor is it difficult. But some part of my notation or how I have defined my functions is messing up the D[f,x] function. ...
9
votes
0answers
108 views

Possible Bug in LinearSolveFunction with Sparse Vectors

Bug introduced in 5.0 and persists through 10.4.1 LinearSolveFunction is new in 5.0 Consider the following set of equations and corresponding variables: ...
1
vote
1answer
27 views

Mathematica Empty Plot FourierSinSeries function

I'm trying to get a plot of different order Fourier series of the function x-1, why does Mathematica give me an empty plot? ...
16
votes
1answer
343 views

What has changed in the Template system in 10.3?

Bug introduced in 10.3 and persisting through 10.4.1 There are couple of issues that are breaking my code after upgrading to 10.3. I wasn't able to narrow all of them down but this is what I've ...
3
votes
1answer
67 views

Calling results of applying f to expr inside NestList

Being new to Mathematica, I try to follow the suggestions of using NestList, Map, Table ...
2
votes
2answers
40 views

Better alternative to Hold/ReleaseHold for postfix application of Monitor

Trying to Monitor a process using the postfix notation, as in Table[Pause[n/10], {n, 5}] // Monitor[#, n] & fails: the ...
6
votes
1answer
67 views

Custom operator form for system functions?

There are some functions for which an operator form would make sense but isn't implemented. For example, I'd like to make this work: RandomSample[3] @ Range[10] ...
5
votes
4answers
239 views

Results in terms of a function

Let's assume I have a function $f(x)=\exp(10x^2)$, i.e. f[x_]:= Exp[10*x^2]. When I differentiate $f$ by evaluating the expression ...
-2
votes
1answer
63 views

Plotting 3-dimensional graphs [duplicate]

I just started Calculus 3 and I thought it would be useful to see images of functions to get used to the transition of visualizing in 3-dimensions. I was wondering how one would go about plotting a ...
0
votes
1answer
466 views

Problem with FindRoot applied to functions

I am having difficulty with the error "is not a list of numbers with dimensions..." when using FindRoot (and other numerical routines in Mathematica) to solve equations numerically when the argument ...
5
votes
2answers
163 views

Get envelope of a set of functions?

I'm new with mathematica and I'm trying to solve a problem. I have a set of functions in the same variable. Let's say the domain is [0,2]. I would like to get an ordered list of the functions ...
3
votes
1answer
52 views

Undocumented “Output” alignment argument to “Column?”

In this SE question, Inheriting Stylesheets when using CreateDocument, I noticed the literal string argument "Output" to Column. ...
0
votes
0answers
90 views

Impose a boundary condition to a function

Background I am trying to impose a boundary condition on a function of two variables $u(x_1,x_2)$. The boundary condition is: $u(x_1,0)=A\cos(\omega x_1)$. The same function in mathematica ...
0
votes
0answers
28 views

Graphing/Plotting multivariate profit function with inequalities

I have the following profit function which I would like to 3Dplot in Mathemathica: Profit = (8c^2-16c*s-10c-4s-3)/(32s+16) , where ...
0
votes
0answers
44 views

How to calculate a continuous function once and access values later?

I have a function that involves a numerical calculation: h[v_]:=NIntegrate[f[x]*Log[p[x, v]], {x, -Infinity, Infinity}] I need to visualize how well a bunch of ...
3
votes
2answers
68 views

Calculate Cumulative Mean and Standard Deviation of a list without FOR loops [duplicate]

I have a simple list mylist={x_1,x_2,...,x_N};. Now I want to map a function over this list, e.g. the Mean and StandardDeviation functions, so that it will give me ...
2
votes
1answer
141 views

Creating a function takes a list and dynamically modifies that list [duplicate]

I'm trying to create a function that uses a dynamic locatorpane to populate a list with the coordinates of user defined locators (added by alt+clicking). This code works fine: ...
0
votes
3answers
71 views

Write complex number in terms of absolute value and phase

I have a long vector and some of the values (19 out of 64) are complex. I got them using the Mathematica Rationalize function, so the complex ones are written in the a+bi form. Is there a function I ...
0
votes
2answers
109 views

How do I get Series[] as a functional, rather than as an expression (i.e. to avoid the dummy variable)?

How can I write an equivalent to Series that doesn't require a dummy variable? Note that the series should be constructed before the evaluation point is supplied, ...
6
votes
0answers
123 views

What is the difference between GenerateDocument and TemplateApply[NotebookTemplate[

Bug introduced in V10.0 and persisting through V10.4 Since V10.3 the bug still remains but additionally the Genarate and ...
0
votes
0answers
10 views

How to connect two tilted lines with a sigmoid curve? [migrated]

Any idea how to connect two tilted lines with a sigmoid curve? The ultimate goal is to get a baseline that is composed of two separate tilted lines ( with known start and end points) with a sigmoid ...
0
votes
0answers
52 views

break down the function

I am using Series function, but I found that it cost too much time. Since the Series function is Taylor expansion and I only need first order, I want to break down the code, so I can make it faster ...
0
votes
1answer
50 views

Why my Function Has no Output Plot?

Below is my commands on a mathematica script to plot a function. In order to see why the function has issue to be plotted, I have tried to plot the intermediate functions one-by-one. It seems that my ...
4
votes
1answer
74 views

How to pass a pair of values to Table function?

I define a function like this: ϕ[t_,ϕ0_,ϕ1_]:=ϕ0+ϕ1/ArcSin[0.97] ArcSin[0.97 Sin[2Pi f(t-0.25/f)]]/.f->30 which generate: $$ \phi (t)=0.754586 \times ...
1
vote
1answer
61 views

How to extract all necessarily code for a function?

Many times when someone pastes a piece of code into SE there are missing values and symbols that the user left out. To prevent this I'm looking for a function that uproots other functions (extract ...
1
vote
0answers
42 views

Is there any way to see a kernel function's code? [closed]

I was using the extremely useful function PrintDefinitions from the GeneralUtilities package and I encountered this: ...
2
votes
2answers
68 views

Why is the square of a differential operator not evaluated automatically?

I defined an operator: py[f_[x, y]] := (I*h*D[f[x, y], y] - x) // Expand (not important, but it represents a simplified component of a quantum momentum in a ...
2
votes
2answers
69 views

Omit argument specification in function [duplicate]

If a function has e.g. 5 input arguments (a,b,c,d,e), how can I omit to specify only argument c, so that its default value is taken, but the other arguments should be passed to the function? E.g: ...
1
vote
1answer
77 views

Excel lookup function? [duplicate]

I have two lists, one for the length of words and another list for the corresponding bonus points. ...
5
votes
4answers
101 views

Using roots to get original equation

I have a list of four rules, that I would like to use to find the original polynomial that produced them. The rules are of the form ...