23 questions linked to/from How to make use of Associations?
132k 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 ...
14k views

### Struct equivalent in Mathematica?

I really miss having something like a struct in Mathematica. I know of (and regularly use) a couple of programming techniques which feel like a ...
3k views

### V10's Operator Forms - what are they good for?

V10 introduces an operator form for several functions perhaps primarily due to their role in queries as part of introducing data science functionality. At first pass it seems a lot of effort to add ...
4k views

### Changing Values in an Association using Map

I am trying to change the value of one key in an association based on the value of another key in that association. So if my association starts as: ...
3k views

### Memoization with pure functions?

Is this possible? If I have a simple function, say: f=If[#>0,1,2]& then for each value of # this will re-evaluate f right? Is it possible to define a ...
682 views

### Reshaping associations, generalization of GroupBy

Let's say we have a set a\of associations: ...
7k views

### Implementing a dictionary data structure

As one learns from a course on data structures, hash maps or dictionaries can be efficient when applied to appropriate tasks. I need a hash map in Mathematica and I've never found it. I'm scratching ...
7k views

### Assigning values to a list of variable names

As part of a calculation I need to do something like this Evaluate[{aaa, bbb, ccc}[[ index]]] = {1, 2, 3, 4, 5} so if index is ...
722 views

### Does Mathematica have Month Range and Day range?

It is known that CharacterRange["a", "z"] gives list of characters from a to z. Does Mathematica have something similar for weekdays and months of the year? ...
334 views

### Create Nested List from tabular data

Im trying to create a nested list from tabular data, then onward into a nested association. I can get part way with the help of this answer but it only works for the first level. Repeated use of this ...
2k views

### Which Object-oriented paradigm approach to use in Mathematica?

Which Object-Oriented Paradigm (OOP) approach to use in Mathematica for: general implementation, or a particular project? There are a lot of related questions and answers in MSE on doing OOP that ...
1k views

### Assigning to multiple variables in a list the values in another list

I have two lists, one contains the variables and the other the corresponding values that the variables should take. ...
232 views

### How does thing[“property”] syntax work?

Many builtin "things" support the (usually undocumented) syntax thing["property"], and usually the available properties can be listed using thing["Properties"] (thing["Methods"] might work too). ...
539 views

### Association and rudimentary object-oriented programming

Doesn't Association provide us rudimentary object oriented programming via constructs like ...
161 views

### Timing: extracting from List VS extracting from Association

I was wondering, why is extracting from an Association slightly faster than extracting from a List? ...
190 views

### Using Associations and Pattern matching in numerical functions possibly broken

It looks like the very young feature of pattern matching (/replacing) within Associations (https://mathematica.stackexchange.com/a/119542/6804), with or without ...
105 views

### How to efficiently write into PackedArrays that are stored in Associations?

Using Association to generate complicated data types is very comfortable, in particular if one uses those tricks from How to make use of Associations?. However, I ...
174 views

### Create tree association using table

Suppose I have a table like the following (This example is simplified, actual table is much larger), it is read from external files: ...
301 views

### Does Mathematica support an unordered set (e.g. hashset) data structure?

Does Mathematica support any data structure representing an unordered set (without multiplicity) of Mathematica expressions? I would like this data structure to support $O(1)$ insertion, deletion, and ...
82 views

### Interdependent SetterBars with symbolic contents

In this question, I learned how to cascade or nest interdependent Setter and SetterBar controls with numerical Ranges. The ...
96 views

### Time complexity to choose the right overload from the memoized function

If we want to save some outputs of the function, we often use the memoization pattern as follows, f[x_]:=f[x]=x f/@Range[10^5] If I call this function many times ...