Concept Taxonomy #198
Description
Hi,
I'd like to offer my contribution to the R track by providing a few concepts.
I didn't see any reference to a roadmap related to this matter.
Is there a concept taxonomy being worked on by anyone?
Here's a first draft of one I've been working on:
| slug | name | blurb | prerequisite | covers | priority |
|---|---|---|---|---|---|
| objects | R Objects | Objects are R fundamental entities | general intro, the assignment operator and naming things | 1 | |
| atomic-vectors | Atomic Vectors | All Values are Vectors | objects | length(), scalar and empty vectors, positional subsetting with [i], c(), seq() | 2 |
| logical-type | Logical Data Type | Using Booleans with Logical Vectors | atomic-vectors | logical constants (TRUE, FALSE), comparison operators and basic logical operators (&, I, !), create with logical(), coerce with as.(), check with is.() | 3 |
| numeric-mode | Numeric Data Type | Using Integers and Floats with Numeric Vectors | logical-type | integer and double types, L suffix, 32 bits constraint, numeric constants (pi, Inf), arithmetic operators, recycling, ":" | 4 |
| character-type | Character Data Type | Using Strings with Character Vectors | numeric-mode | basic string manipulation, nchar(), maybe strsplit(), character constants (letters, LETTERS etc.) | 5 |
| missing-value | Missing Value | Dealing with Missing Values | character-type | NA (maybe NaN), NULL, is.na(), is.null(), the na.rm argument | 6 |
| names-attribute | Attributes and Names | Naming things is hard | missing-value | attributes(), attr(), names(), subsetting with ["name"] | 8 |
| functions | Functions | Let’s do stuff and automate it | names-attribute | arguments, named arguments, formals, body, return keyword, "…" | 7 |
| class-attribute | Classes | R has one of the most flexible class system | functions | class(), unclass(), generic functions (S3) and method dispatch, special double dispatch for grouped generic functions | 14 |
| conditions | Conditions | Control your code execution with if statements | names-attribute | If, else, lazy evaluation with && and ||, xor(), precedence, identical(), all(), any() | 9 |
| iterations | Iterations | Repetitive code execution with loops | conditions | for, in, seq_along(), while, repeat, next, break | 10 |
| exceptions | Exceptions | Handling errors and recovering | functions | stop(), stopifnot(), warning(), try() | 15 |
| factors | Factors | Integer representation or characters | missing-value | ordered and unordered factors, levels attribute, stringsAsFactors argument, maybe cut() | 19 |
| dim-attribute | Dimensions | Dimensions of an Object | names-attribute | array, matrix, subsetting with [i, j, k], dimnames attribute | 20 |
| switch | Switch | Select One of a List of Alternatives | missing-value | on character or numeric expressions | 18 |
| lists | Lists | Lists are Recursive Vectors | atomic-vectors | subsetting with [[ and $ | 11 |
| tabular-data | Tabular Data | Lists superpowers | lists, class-attribute | data.frame, row.names attribute, cbind(), rbind(), subsetting with [row, col] | 12 |
| selection | Subsetting | Chirurgical operations | tabular-data | Summary of [, [[, $ , sort(), order(), which() and %in% for subsetting | 13 |
| apply-functions | Apply Functions Family | Apply functions are here to help you vectorize your code | functions, iterations, lists | lapply, sapply, vapply etc. | 16 |
| regex-functions | Regex Functions Family | Pattern Matching and Replacement | functions | grep(), grepl(), regexpr(), gregexpr(), regexec(), gregexec(), sub(), gsub() maybe stringr:: | 17 |
| raw-type | Raw Data Type | Store raw bytes | character-type | strtoi(), charToRaw() - there’s actual use case in exercises so it might deserve higher priority but seems somewhat advanced | 22 |
| environments | Environments | Lexical and Dynamic Scoping | functions | current, global, closure, <<-, namespace | 21 |
Additional concepts that could also be introduced:
- pipes (base R and magrittr)
- maps (purrr)
I don't really know at what point I would be a good idea to introduce recursion (functions, lists, iterations...).
Of course this is all work in progress and need much more thoughts, but I'd like to have your feedback before I look further into this (on the concepts themselves - definition, scope and order, as well as the method as I'm new to Exercism)
Major references: