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

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0answers
24 views

valuation to a function using a list [duplicate]

What I want to do is to evaluate a function as shown below: LessQ[n_] := LessQ[n] = l[n] < 61 In some cases, when I am sure that on a list the ...
2
votes
1answer
129 views

making a function of fit results

I have 13*25 datasets consisting each of around 40 points. They are all linear I can easily fit them using fit function but my problem is when I want to call them I want them to be functions. I want ...
4
votes
1answer
250 views

How to check if a given expression is an “explicit algebraic number”?

The documentation for PossibleZeroQ says: With the setting Method...
5
votes
2answers
162 views

How to check an algebraic number for membership in a list

I need to check an algebraic number for membership in a list of algebraic numbers. The numbers can be expressed in different forms (combinations of radicals, Root ...
-1
votes
2answers
309 views

How do I generate a table of data points from a function and add random noise? [duplicate]

I am trying to generate a table of data for the function: ...
2
votes
2answers
198 views

Restarting an Animate animation after variable in Manipulate changes

I've been trying to restart an animation after variables change from Manipulate PopUpMenus. My animation takes the form: ...
1
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1answer
183 views

Derivative inside a function

I am trying a problem that should be simple: to create a function that contains a derivative. I need to do a more complex example, but even with the simplest I'm having trouble: Let's consider ...
7
votes
2answers
148 views

How do I invoke the default complexity function?

Documentation on ComplexityFunction says: With the default setting ComplexityFunction->Automatic, forms are ranked ...
1
vote
1answer
150 views

Recursive function taking functions as arguments

I'm trying to implement Lie brackets and derivatives of nth order. For doing this, I've stumbled upon something I don't understand. Here is an illustration: First I define the functions: ...
9
votes
1answer
365 views

Is it possible to find a limit of a sequence given by its recurrence relation?

I need to calculate a limit of a sequence given by its recurrence relation. I tried the following: ...
6
votes
3answers
298 views

How to get the correct answer when solve this equation?

I want to find the values of the parameter $m$ to the graph of the funtion $$x^4 - 2 m x^2 + m + 1$$ has three extremal points make an equilateral triangle. I tried ...
7
votes
2answers
139 views

Change some option of a function when calling it [duplicate]

Say I have defined some function like f[p_] := Plot[Sin[p*x], {x, 0, 2 Pi}] Now in most cases, I just need to specify the value of ...
4
votes
2answers
183 views

Using Element[]

Can the Element[] function only be used for the domains given in the documentation? I am trying to use it to determine if a value is contained in a previously defined list. Thanks!
-1
votes
1answer
243 views

How to define a pure function with a Module?

I was not able to use a self defined (using Module and For loops) piecewise function to fit data. It seems that the problem is that I have to define a pure function. I would like to learn how to ...
1
vote
1answer
148 views

Find a sequence of integers which give max in each step

I would like to write a program in Mathematica to look for the integer $n$ such that the following definition holds for any $1 < m < n $ $$\frac{f(n)}{f(m)}>1+\frac{\log(n/m)}{\log(n) ...
24
votes
1answer
231 views

What does Internal`InheritedBlock do?

What does the function Internal`InheritedBlock do? How is it different from the regular Block?
0
votes
1answer
65 views

Have the kernel load a user-defined function by default [duplicate]

I wrote a very simple function that I would like to act as if it were one of the default functions that came with Mathematica, so that you don't have to load or import any package before you make use ...
6
votes
1answer
114 views

create function that behaves like continuedFraction [duplicate]

I'm just starting to learn Mathematica and I got stuck at this question. This a noob question but please help. I need to define a function named continuedFraction that takes user input of type list ...
29
votes
5answers
949 views

Why is there no PositionFunction in Mathematica?

Too often I have seen the programs of inexperienced users greatly slowed by using Position in an iterative fashion, when far faster would have been to compute a ...
3
votes
2answers
763 views

Function returning Null along with other unexpected expressions

When I use some function, at the end along with the output I get some NULLs returned that I don't understand the reason for and are highly undesirable. For example, when I define the reversal of list ...
1
vote
0answers
85 views

Does Graphics`Mesh`SimplePolygonQ[] work for you?

Graphics`Mesh`SimplePolygonQ is an undocumented function. I'm using Mathematica 7, and when I try: ...
2
votes
4answers
1k views

How can I create a list of functions?

Can anyone tell me, how to create a list of functions? I've tried the following code, but it doesn't work. ...
2
votes
1answer
116 views

Flat function with repeated sequence

There are functions like Join[ ] that accept a variable number of arguments. Join is a flat function, as the order of arguments ...
0
votes
1answer
77 views

What does Binomial return for non-integer arguments?

Mathematica returns values for non-integer arguments passed to Binomial. What is the definition of Binomial for such continuous ...
9
votes
1answer
192 views

Creating a NearestFunction that returns an index

I use Nearest repeatedly for large data sets. For example pts = RandomReal[{-1, 1}, {1000, 3}]; Nearest[pts, {0, 0, 0}] I ...
3
votes
0answers
164 views

Mathlink and multithreading

In order to make my computations faster I have developed a C/C++ application calling Mathematica kernel and performing many operations using Mathematica functions for equation solving. Now I want to ...
31
votes
2answers
1k 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 ...
2
votes
1answer
364 views
9
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1answer
231 views

Apply a Function Pairwise

I'm new to Mathematica I'd like to apply Mean pairwise to a list to achieve the following. ...
1
vote
1answer
163 views

How to send a function definition to MathLink from C/C++?

In this tutorial some MathLink concepts are introduced. At page 33 in the last lines the author is talking about sending to MathLink a function definition like ...
4
votes
2answers
363 views

Cannot call custom function loaded from script using C/C++ MathLink

I am using MathLink with C/C++ on a Unix system in order to call a Mathematica (version 9) function and get the result. The function I need to call is a personal function of mine ...
6
votes
1answer
113 views

How does `LongestCommonSubsequence` work?

When I recently came across this posting about LongestCommonSubsequence I was curious about how the function worked. ...
15
votes
2answers
249 views

What are Root objects with multiple polynomials?

In Mathematica 9 a new flavor of Root object with multiple polynomials was introduced. For example, ...
10
votes
1answer
129 views

How do I expand StirlingS2[n, 10] in terms of elementary functions?

I know that it is possible to expand StirlingS2[n, 10] in terms of elementary functions of n. I tried ...
1
vote
1answer
318 views

Finding n-th term of a sequence of functions

Lets say, I have the following series of functions, $f_1=a+1$ $f_2=a^2+2a+1$ $f_3=a^3+3a^2+3a+1$ Assume that $f_4, f_5,$ and $f_6$ are also known. However $f_n$ is not known as a function of $n$. ...
13
votes
1answer
288 views

How do I get a general form for n-th derivative of a function? [duplicate]

I tried the following but it basically returns unevaluated: ...
1
vote
1answer
211 views

Notebook UI: Autocompletion - Display function arguments when typing?

Is there a setting to display the required arguments of a function when typing as Visual Studio, Matlab, etc. does?
2
votes
1answer
135 views

Cannot run Mathematica C-interfacing examples 'factor'

I am trying to run a Mathematica example concerning Mathematica interfacing issues with C programs. In particular I am trying to call a Mathematica function from C. Example ...
0
votes
1answer
62 views

Don't pollute outside context when solving equation from the outside

This code works fine only if a is not defined in the outside context: ...
1
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2answers
95 views

Calling blank arguments using enclosing functions

Is there a way to call a function and have that function use an argument defined in an enclosing function? e.g., ...
2
votes
1answer
934 views
11
votes
1answer
1k views

Write C/C++ programs calling Mathematica functions

I need to write a C/C++ program and call some functions in Mathematica especially those like Solve or NDSolve. The problem is ...
3
votes
2answers
136 views

Generating a list of pure variables

I want to pass a list of pure variables to a function, in which the ordering of the variables matters. For instance, if I want a palindrome, my function might be: ...
2
votes
2answers
622 views

distance between two curves

I try to compute the distance between two curves. I use the EuclideanDistance to do that. Here my code: ...
0
votes
1answer
297 views

Can Mathematica check if two expressions give the same output for integer input?

Let me give the background for this question. I'm using WebAssign to assign homework problems, and WebAssign has a built-in mechanism which can grade problems using Mathematica commands. For ...
0
votes
1answer
111 views

Can I force a function to quit and return some value after a certain amount of time has passed during its evaluation?

Imagine I provide some random input to function like FindInstance[], and I observe that, despite the existence of good solutions, the function will, with some ...
1
vote
1answer
1k views

How do I define the domain of a function?

I have a function of two variables, f[x_, y_], and I would like to restrict the domain to values of x and ...
1
vote
3answers
508 views

Sqrt — how to get negative branch?

One of the many attractions of Mathematica is that integers are generally treated as exact symbolic entities, and not just as numbers. I was just playing with Sqrt, and was puzzled by what appeared to ...
5
votes
5answers
2k views

How to sum over a List

list = {11.5575, 11.397, 5.52734, 4.0878, 2.54815, 1.86652, 2.55028, 2.14952, 1.6242, 1.34117} I have a list of numbers. How do I make a function that creates a ...
0
votes
1answer
318 views

Using undefined function in an expression

I want to use undefined functions in expressions to be simplified. For example. I want mathematica to simplify this input $(f^{\prime\prime}(t),g^{\prime\prime}(t))\cdot (-g^\prime(t),f^\prime(t)) $ ...