Linked Questions

602 votes
19 answers
156k views

Where can I find examples of good Mathematica programming practice?

I consider myself a pretty good Mathematica programmer, but I'm always looking out for ways to either improve my way of doing things in Mathematica, or to see if there's something nifty that I haven't ...
45 votes
4 answers
5k views

Can a function be made to accept a variable amount of inputs?

I have a function that takes two inputs and processes them for a single output. What I need is one that can take a varying number of inputs. and process them to a single output. Is this possible in ...
Nothingtoseehere's user avatar
20 votes
1 answer
324 views

How to get Cases to wrap results in an arbitrary head?

A number of functions provide for results to be wrapped in an arbitrary head. This is very important in cases where the results should not be evaluated. Take Level...
Mr.Wizard's user avatar
  • 272k
16 votes
2 answers
688 views

f[arg1, arg2,...,argN] vs. f[{arg1, arg2,...,argN}]

I am trying to reproduce the API of a function (written in R) that accepts an arbitrary number of arguments and handles it the same way as it would handle a single argument that is a list of different ...
Eric Brown's user avatar
  • 4,426
14 votes
9 answers
2k views

How can a power of 0 or 1 be replaced?

Consider this given example for ReplaceAll 1 + x^2 + x^4 /. x^p_ -> f[p] This returns ...
Sumit's user avatar
  • 15.9k
12 votes
9 answers
562 views

List manipulation - adding last element of sublist to each sublist

If I have the following list: {{}, {1, 2}, {}, {2, 4, 3}, {5, 4, 3, 2}, {}} How can I add the last element of each sublist to each sublist? The results should ...
lio's user avatar
  • 2,396
10 votes
4 answers
2k views

Function argument to default under certain condition

Inspired by this and this question (and how I handle this in practice), what is the best way to default a function value when a certain condition is met? For example, if a function is defined as: <...
kale's user avatar
  • 10.9k
9 votes
5 answers
465 views

How to distinguish between lists and values?

I have a (hopefully small) problem with some numerical integration algorithm, more specifically I want to integrate the imaginary part of a complex valued function, e.g. ...
user13655's user avatar
  • 377
9 votes
3 answers
2k views

Function with zero or one arguments

Is there a neat way to define a function with a single optional argument that defaults to an empty sequence? For example, suppose I want to define a wrapper for ...
Stephen Powell's user avatar
9 votes
3 answers
760 views

Generalization to AllTrue, AnyTrue and NoneTrue

I am wondering if there is a natural Mathematica way to generalize those functions. To be specific, All three functions AllTrue, ...
Sungmin's user avatar
  • 2,305
5 votes
2 answers
304 views

Function pattern to support listed and non-listed arguments [duplicate]

I often want to write functions that take as an argument either a) a rule or b) a list of rules. As an example, when using Replace with just one rule, it does not ...
Theo Tiger's user avatar
  • 1,273
4 votes
2 answers
397 views

Generating all permutations of labels in an expression

I have some very long and complex expressions which involve a set of $n$ variables, and I want to be able to permute the labels of the variables. I will give a simple example, instead of my awful ...
Jojo's user avatar
  • 1,278
3 votes
1 answer
188 views

Optional argument as a correction of a main argument

Let's consider a function f[a_,b___] I want that if I input only one argument I get f[a]=a but if I input 2 arguments I ...
Giancarlo's user avatar
  • 712