For questions on writing functions (pure or using Set/SetDelayed) for any purpose, including the features that may be incorporated in those functions, such as options, patterns and conditions.

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2
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2answers
146 views

How to get `Series` to recognize user-defined function has pole

Edit for clarity: How does Mathematica's function Series know that Gamma[x] has a pole at ...
2
votes
1answer
793 views

Why is either Listable or HoldFirst not working?

Starting with a fresh kernel, I evaluate the following: ...
2
votes
1answer
109 views

Having variables appear aqua in user defined function [duplicate]

In many of the inbuilt mathematica function, variables appear aqua like in: However, when creating your own function, variables no longer have that green coloring and are instead colored like an ...
2
votes
2answers
96 views

Creating function with matrix argument

I am completely new to programming, so I apologize in advance for a stupid question. I want to program an algorithm for computing invariant factors of a finitely generated abelian group, so in ...
2
votes
1answer
200 views

Requiring NumericQ in Pure Function

Potential duplicate, but doesn't seem to solve my problem: Using patterns in pure functions I have a function that returns an InterpolatingFunction, and it works ...
2
votes
2answers
566 views

Recursive formula involving a piecewise function

I am trying to construct a recursion, g[t], where g[t] = a[t] if g[t-1] = 1 ...
2
votes
2answers
302 views

Working around behaviour of EdgeRenderingFunction

One can make graphs GraphPlot[{1 -> 2, 2 -> 3, 3 -> 4, 4 -> 5, 5 -> 1, 1 -> 1, 5 -> 5}] and one can generalize the input such that one ...
2
votes
1answer
47 views

Passing a list to a nested vector function

In order to apply a newton-rhapson algorithm to solve a set of nonlinear vector equations such as these, f[x_, y_] = {x^2 - 3*y + 6, (y + 1)^2 - x - 33} I need ...
2
votes
1answer
46 views

combine two definitions into one [closed]

Suppose I have two definitions of a function such as ...
2
votes
3answers
96 views

How to test a condition for a list and output all the expression that is true?

Suppose that I have a list lis={x-y,x+y,x*y}; and a function f[a_,b_]:=#/.{x->a,y->b}& I want to output all the ...
2
votes
1answer
64 views

What are the applications of using functions whose heads are also functions?

I noticed that it is possible to construct something like f[x][y]. Displaying this in TreeForm indicates that this expression ...
2
votes
1answer
80 views

How do I tweak the input assistant to use string completion on my own functions? [duplicate]

I would like to be able to use Mathematica's string completion feature for subvalues of my own functions. I tend to go for functions that follow the pattern ...
2
votes
2answers
92 views

Adding a tree to a list of trees within a loop [duplicate]

I'm trying to write a function which for a list of trees checks if a given tree is isomorphic with any of the listed, and if not - adds it to the list. I tried to use both ...
2
votes
1answer
95 views

Generating list of functions from list of expressions

I know how to create a function from concrete expression like Function[{x, y}, x^2 + y^2] But what if I have a list of expressions list1 and I know the set of ...
2
votes
1answer
154 views

How to define a function of z[bar], etc

Using Displaying index as subscript on output: e.g. C[i] -> C_i with Notation[...] or Interpretation[..]? I have often ended up wanting to define functions of annotated variables to better match my ...
2
votes
2answers
1k views

Composing two functions in Mathematica [duplicate]

Possible Duplicate: Composition of mappings not working as expected I am new to Mathematica and I am having trouble defining a certain composition of functions. Let ...
2
votes
1answer
267 views

How to override `?NumericQ`

I have a function myFunc which I is to be displayed cleanly if arguments are symbolic, but which can also be numerically evaluated. I do this by defining a ...
2
votes
1answer
218 views

How do I determine if there's an arithmetic sequence within a list? [duplicate]

Possible Duplicate: find subsequences of constant increase Given an arbitrarily long list of integers (let's say they are sorted), how would one determine if any 3 (or more) of those ...
2
votes
1answer
117 views

How to properly define this function of function

I encountered real problem at first, and here is the toy example variable argument stored some expression that is generated from other parts of the program. I ...
2
votes
1answer
49 views

Defining function [duplicate]

ver1 = 2 x verf[x_] := ver1 verf[3] Result : 2 x Expected Result : 6 In the above code ...
2
votes
1answer
63 views

Manipulating unevaluated expressions in nested function calls

This is a follow-up to my earlier question: Passing an unevaluated part of an association to a function I'm trying to create a modular dashboard that controls sound volume of an audio system ...
2
votes
1answer
55 views

Appending Delayed Evaluation

I have a function that need to be summed over all parameters given in a separate list. f[x_,y_,z_,n_,i_]:= (*Some function*); list={{n1,i1},{n2,i2},...}; I need ...
2
votes
1answer
50 views

Strange behavior when defining a symbol/function pointwise

I am well aware of the fact that floating point number have finite precision, so one needs to be careful when comparing them. Still, I find it disturbing/surprising that the following input into ...
2
votes
1answer
480 views

What is the meaning of two square brackets in function definition? [duplicate]

I came along the following function definition f[a_, b_, c_][r_] = ... with some function on the right hand side. Is this equivalent to ...
2
votes
1answer
283 views

How to make a function from body with variable number of arguments?

Suppose I have an UNKNOWN function, which generates formulas with given number of x[i]. ...
2
votes
1answer
43 views

Linear function on strings using UpValues

I have two functions Sup and Sdown that take a string of letters with allowed characters ...
2
votes
2answers
122 views

How to make functions from datasets

I have a csv that encodes the results of plugging certain parameters (say, A and B) into certain functions (say, ...
2
votes
1answer
114 views

Defining a rule with functions of arbitrary arguments

I have a set of "functions operators", say A1[u],A2[u],A3[u],and I would like to define a rule such that, for instance, (x*A1[u1]).(y*A2[u2]) returns ...
2
votes
1answer
665 views

Defining Piecewise Functions [duplicate]

I'm having trouble defining piecewise functions. What I have so far is a function that outputs something in a suitable format for Piecewise: ...
2
votes
1answer
220 views

Issue with Coefficient command [closed]

I'm trying to used the Coefficient command to extract the numerical values in front of a Chebyshev polynomial. I know that there is a numerical way to do this, presented in numerical recipes, which I ...
2
votes
1answer
220 views

User-defined Distance Functions with extra parameters [duplicate]

The Nearest function accepts a customized distance function. For example, a simple case that works well is ...
2
votes
1answer
136 views

Implementing a For (?) or series or loop (?) for individual results for every x to n

I'm working on improving a modeling formula and have spreadsheets worth of data to use, but my work so far has been quite tedious. I'm essentially pulling 20 rows of data from each separate sheet of a ...
2
votes
1answer
335 views

Defining a function that handles Dynamic arguments similar to Built-ins

Firstly please note that I'm using simply Dynamic behavior to illustrate my question, I'm not asking how to move a Disk or make ...
2
votes
1answer
119 views

Syntax f[x_][y_]

Need to understand the principle of the distinction between f[x_,y_] and f[x_][y_] It seems also that z[x_, y_][a_, b_, c_][α_, β_] := a (x + y)^b + c/(α-β) ...
2
votes
0answers
49 views

First position of incremental series

I am still a beginner and maybe I want to do something too complicate! After 29 cycles I obtained the following events list: ...
2
votes
2answers
46 views

Deciding whether the return value of a function is defined based on its input [duplicate]

I have been met with the following problem: I have defined the following: myFunc[e_Integer]; That means, if I call: ...
2
votes
0answers
68 views

Automating game simulation, using previous results [closed]

Based on this question on MSE, I would like to simulate a game whereby player $2$ enters a number, so as to test the strategy. The basis for this is the factor game online here. ...
2
votes
0answers
36 views

Unexpected behavior from Return called in a Block [duplicate]

I like to write functions that dispose of failure cases early, before they do the main calculation, but I don't like to write cascading If statements. Here is a toy ...
2
votes
0answers
90 views

Construct single InterpolatingFunction from a mathematical combination of other IF's

Let's say I have an interpolated function f, like I might get as the solution to an NDSolve: ...
2
votes
0answers
206 views

Oddify an even function and vice versa? [closed]

I want to know how to construct a function in Mathematica which would produce even analog of odd function and vice versa in closed form? The mathematical definitions are as follows: ...
2
votes
1answer
81 views

Using HoldFirst but not wishing to hold everything

I have a DynamicModule in which I go through some data analysis and keep or reject the results. Here is a toy example of what I am doing. ...
2
votes
0answers
83 views

How to make a new analytic function work seamlessly with Mathematica's analysis functions?

I am defining a new analytic function of six variables. I have algorithms to evaluate it numerically, and have amassed a large catalog of analytic properties. It is easy for me to program the ...
2
votes
0answers
22 views

In a Function, how to Ensure Code Runs Prior to an Abort [duplicate]

Is there a way to set aside some code in a function that will be triggered to run if the evaluation of the function is aborted by a user? Specifically, I have a function that has to open a log file to ...
2
votes
0answers
83 views

Function that assigns properties [duplicate]

I want to create a function that creates and assigns properties to a symbol. In theory this would behave similarly to the NonzeroValues property of ...
2
votes
0answers
281 views

Positive integrand giving negative answer

I'm integrating a positive function f(t) times sin(t) from 0 to pi/5 and get -38. Actually f is slightly negative for a short time (smallest value ~ -0.0005), but far from enough to explain this. ...
2
votes
0answers
37 views

Detecting a more general pattern [duplicate]

I need a function that, given 2 patterns, determines if the first pattern is more general than the second (i.e. that any expression successfully matched by the second, will be successfully matched by ...
2
votes
0answers
137 views

correct usage of ParallelTable

I am trying to parallelize my script. Here is a MWE of how I have done it: ...
2
votes
0answers
96 views
2
votes
0answers
95 views

How can this function's options be used in different places? [duplicate]

I wrote this function to make a ListPlot where the points are colored by a third argument. ...
2
votes
1answer
203 views

Difference between function definitions [duplicate]

Possible Duplicate: Functions vs. patterns I thought about describing the context in which I faced this problem, but I figured it is general enough and clear enough to pose it as it is. ...