Linked Questions

I haven't seen this question specifically addressed before in this site, although some hints and traces have been given, for instance, here: Pass by reference for an option argument Does pass-by-value ...

An example will be most specific: func[list_, column_] := list[[All, column]] = Map[#*2 &, list[[All, column]]]; This throws errors. I want to avoid doing ...

Sometimes I'd like to make a function, which would take an argument "by reference" instead of usual "by value". This is semantically similar to what e.g. AppendTo ...

For example, I defined a user function with a module and what this function does is take the values of two global variables ga and ...

I'd like to write a function, that would take a matrix as an input parameter and would change it by multiplying one of its rows by a factor. I try to do it in the following way: ...

I have a custom function like this stringLength[string_] := StringLength[ ToExpression[StringJoin[ToString /@ {del, string}]] = StringDelete[string, " "]] ...

read some related posts and found no solution. For a list defined like this m = {0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.9, 1.0, 1.5, 1.6}; when I define this function ...

I can't transform a simple code into a function. The function should take an integer and return a list of digits in a factorial number system: ...

I'm currently trying very hard to assign a variable inside a function. Therefore I'm using a function like this, which should reassign a predefined variable. ...

Can someone explain the principles underlying the following behavior. I define the list testD, and then use a Do loop to change values in the list (I realize there are smarter ways but they don't fit ...

I want to create a function that when it is called clears the value of a parameter. For example I want to keep the value of a parameter and then clear its valueby calling a function: ...

Assuming variable x is a long list, which needs 1GB memory to store. I want to modify x in a function, such as let x[[10]]=1, using ...

I have written a function to assign values to a matrix putConj[arr_, i_, j_, val_] := Block[{}, arr[[i, j]] = val; arr[[j, i]] = val\[Conjugate]; ] This ...

As you may already know, Mathematica is a wonderful piece of software. However, it has a few characteristics that tend to confuse new (and sometimes not-so-new) users. That can be clearly seen from ...

Given a function with the attribute HoldFirst, HoldAll or similar, and a variable, list, how ...