# Category:Phix

**Phix**

This

**programming language**may be used to instruct a computer to perform a task.

Official website |
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Execution method: | Interpreted or compiled |
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Garbage collected: | Reference Counting |

Parameter passing methods: | By copy-on-write |

Type expression: | Explicit |

Type checking: | Dynamic, Static |

Lang tag(s): | phix, Phix |

See Also: |

Phix is a self-hosted hybrid interpreter/compiler, developed by Pete Lomax. It is very easy to use, and similar to Euphoria.

A single 16MB download contains a pre-compiled executable, all the sources, and* everything *needed to recompile them, in about 15 seconds. The download also contains a full-featured programmer's editor and 130+ demo programs.

Perhaps the most striking feature of Phix is that it has just five builtin data types:

<-------- object ---------> | | +-atom +-sequence | | +-integer +-string

Despite such apparent simplicity, or perhaps precisely because of it, Phix programs are pretty fast - not quite achieving the runtime performance of C or assembly, but making up for it with a very fast edit/run cycle and proper human-readable messages should anything go wrong (even in shipped pre-compiled executables). Sequences are the real powerhouse of Phix. The one type covers lists, queues, tables, trees, and arrays, with strings being the subset that is array of character. They can grow and shrink automatically without any memory management overhead. For example if `s="food"` then `s[2..3]="e"` makes `s` "fed", and then `s[2..1]="east"` makes `s` "feasted".

Phix applies the principle of least surprise, for instance in some languages `myproc(list)` or `res = myfunc(list)` can mangle list, whereas in Phix if you actually want that to happen you would code `list = myproc(list)` (and myproc would need to become a function) or `{res,list} = myfunc(list)`. Likewise 1/2 is 0.5 (not 0, unless you explicitly ask for the floor()) and 0-1 is -1 (not +MAXINT). A core tenet is that for any line of code there is one and only one possible interpretation of it, and said meaning is utterly intuitive. True fact: the given answer for the question "describe what f(a++) does" in "More Exceptional C++" lists 4 possibilities for f, and 3 for a (so 12 in total) and uses the phrase "could mean just about anything" not once but twice - shudder.

Phix is not inherently object orientated, but achieves many of the claimed benefits, yet in a much simpler way. In fact I have been looking for * proof* that object orientation actually improves productivity compared to other paradigms for decades, and never found it. Not to say that I won't support it, but I certainly won't enforce it. One other thing I have never found is a "good object orientated design", and reached the conclusion that mythical creature simply does not exist, at least not as a separate entity as opposed to some ethereal quality of the finished code. Feel free to argue that one on User_talk:Petelomax. Phix offers perfectly decent encapsulation at the file level, proving that is not the sole purview of oo, implements polymorphism far more elegantly than C-based languages and far safer than duck-typed languages, and as for the third pillar of oop, inheritance, well isn't the current mantra "favour composition over inheritance"?

The fundamental goal of Phix is to make debugging easier, a whole subject area that does not seem to get the attention it deserves, despite several studies finding that most programmers actually spend between 70 and 90% of their time debugging. (Most of us tend to think that getting just-written code to work is somehow not debugging, but that bloke with a clipboard stood behind you would disagree.)

## See also[edit]

## Subcategories

This category has the following 4 subcategories, out of 4 total.

## Pages in category "Phix"

The following 1,018 pages are in this category, out of 1,018 total.

### A

- A* search algorithm
- A+B
- Abbreviations, automatic
- Abbreviations, easy
- Abbreviations, simple
- ABC Problem
- Abundant, deficient and perfect number classifications
- Accumulator factory
- Ackermann function
- Addition chains
- Addition-chain exponentiation
- Address of a variable
- AKS test for primes
- Align columns
- Aliquot sequence classifications
- Almost prime
- Amb
- Amicable pairs
- Anagrams
- Anagrams/Deranged anagrams
- Angle difference between two bearings
- Animate a pendulum
- Animation
- Anti-primes
- Append a record to the end of a text file
- Apply a callback to an array
- Apply a digital filter (direct form II transposed)
- Arbitrary-precision integers (included)
- Archimedean spiral
- Arena storage pool
- Arithmetic coding/As a generalized change of radix
- Arithmetic evaluation
- Arithmetic-geometric mean
- Arithmetic-geometric mean/Calculate Pi
- Arithmetic/Complex
- Arithmetic/Integer
- Arithmetic/Rational
- Array concatenation
- Array length
- Arrays
- ASCII art diagram converter
- Assertions
- Associative array/Creation
- Associative array/Iteration
- Atomic updates
- Average loop length
- Averages/Arithmetic mean
- Averages/Mean angle
- Averages/Mean time of day
- Averages/Median
- Averages/Mode
- Averages/Pythagorean means
- Averages/Root mean square
- Averages/Simple moving average
- AVL tree

### B

- Babbage problem
- Bacon cipher
- Balanced brackets
- Balanced ternary
- Banker's algorithm
- Barnsley fern
- Base58Check encoding
- Base64 decode data
- Base64 encode data
- Benford's law
- Bernoulli numbers
- Best shuffle
- Bilinear interpolation
- Binary digits
- Binary search
- Binary strings
- Birthday problem
- Bitcoin/address validation
- Bitcoin/public point to address
- Bitmap
- Bitmap/Bresenham's line algorithm
- Bitmap/Bézier curves/Cubic
- Bitmap/Bézier curves/Quadratic
- Bitmap/Flood fill
- Bitmap/Histogram
- Bitmap/Midpoint circle algorithm
- Bitmap/Read a PPM file
- Bitmap/Write a PPM file
- Bitwise operations
- Boids
- Boolean values
- Box the compass
- Brace expansion
- Brownian tree
- Bulls and cows
- Bulls and cows/Player
- Burrows–Wheeler transform

### C

- Caesar cipher
- Calculating the value of e
- Calendar
- Calendar - for "REAL" programmers
- Call a foreign-language function
- Call a function
- Call a function in a shared library
- Cantor set
- Card shuffles
- Carmichael 3 strong pseudoprimes
- Cartesian product of two or more lists
- Case-sensitivity of identifiers
- Casting out nines
- Catalan numbers
- Catalan numbers/Pascal's triangle
- Catamorphism
- Chaocipher
- Chaos game
- Character codes
- Chebyshev coefficients
- Check Machin-like formulas
- Check that file exists
- Cheryl's Birthday
- Chinese remainder theorem
- Chinese zodiac
- Cholesky decomposition
- Chowla numbers
- Church Numerals
- Cipolla's algorithm
- Circles of given radius through two points
- Closest-pair problem
- Closures/Value capture
- Collections
- Color of a screen pixel
- Color quantization
- Color wheel
- Colour bars/Display
- Colour pinstripe/Display
- Colour pinstripe/Printer
- Combinations
- Combinations and permutations
- Combinations with repetitions
- Combinations with repetitions/Square Digit Chain
- Comma quibbling
- Command-line arguments
- Commatizing numbers
- Comments
- Compare a list of strings
- Compare sorting algorithms' performance
- Compile-time calculation
- Compiler/AST interpreter
- Compiler/code generator
- Compiler/lexical analyzer
- Compiler/syntax analyzer
- Compiler/virtual machine interpreter
- Compound data type
- Concurrent computing
- Conditional structures
- Conjugate transpose
- Constrained random points on a circle
- Continued fraction
- Continued fraction/Arithmetic/Construct from rational number
- Convert decimal number to rational
- Convert seconds to compound duration
- Conway's Game of Life
- Copy a string
- Copy stdin to stdout
- Count in factors
- Count in octal
- Count occurrences of a substring
- Count the coins
- Cramer's rule
- CRC-32
- Create a file
- Create a two-dimensional array at runtime
- Create an HTML table
- Create an object at a given address
- Create an object/Native demonstration
- CSV data manipulation
- CSV to HTML translation
- Cumulative standard deviation
- Currency
- Currying
- Curve that touches three points
- CUSIP
- Cut a rectangle
- Cycle detection

### D

- Damm algorithm
- Data Encryption Standard
- Date format
- Date manipulation
- Day of the week
- Deal cards for FreeCell
- Death Star
- Decimal floating point number to binary
- Decision tables
- Deconvolution/1D
- Deconvolution/2D+
- Deepcopy
- Define a primitive data type
- Delegates
- Delete a file
- Deming's Funnel
- Department Numbers
- Detect division by zero
- Determinant and permanent
- Determine if a string is numeric
- Determine if only one instance is running
- Determine if two triangles overlap
- Dice game probabilities
- Digital root
- Digital root/Multiplicative digital root
- Dijkstra's algorithm
- Dinesman's multiple-dwelling problem
- Dining philosophers
- Discordian date
- Display a linear combination
- Diversity prediction theorem
- DNS query
- Dot product
- Doubly-linked list/Definition
- Doubly-linked list/Element definition
- Doubly-linked list/Element insertion
- Doubly-linked list/Traversal
- Dragon curve
- Draw a clock
- Draw a cuboid
- Draw a pixel
- Draw a rotating cube
- Draw a sphere
- Draw pixel 2
- Dutch national flag problem
- Dynamic variable names

### E

- Eertree
- Egyptian division
- Egyptian fractions
- EKG sequence convergence
- Element-wise operations
- Elementary cellular automaton
- Elliptic curve arithmetic
- Emirp primes
- Empty directory
- Empty program
- Empty string
- Enforced immutability
- Entropy
- Entropy/Narcissist
- Enumerations
- Environment variables
- Equilibrium index
- Ethiopian multiplication
- Euler method
- Euler's identity
- Euler's sum of powers conjecture
- Evaluate binomial coefficients
- Even or odd
- Events
- Evolutionary algorithm
- Exceptions
- Exceptions/Catch an exception thrown in a nested call
- Executable library
- Execute a Markov algorithm
- Execute a system command
- Execute Brain****
- Execute HQ9+
- Execute SNUSP
- Exponentiation operator
- Exponentiation order
- Extend your language
- Extensible prime generator
- Extract file extension
- Extreme floating point values

### F

- Factorial
- Factorial base numbers indexing permutations of a collection
- Factors of a Mersenne number
- Factors of an integer
- Farey sequence
- Fast Fourier transform
- Faulhaber's formula
- Faulhaber's triangle
- Feigenbaum constant calculation
- Fibonacci heap
- Fibonacci n-step number sequences
- Fibonacci sequence
- Fibonacci word
- Fibonacci word/fractal
- File extension is in extensions list
- File input/output
- File modification time
- File size
- Filter
- Find common directory path
- Find first and last set bit of a long integer
- Find largest left truncatable prime in a given base
- Find limit of recursion
- Find palindromic numbers in both binary and ternary bases
- Find the intersection of a line with a plane
- Find the intersection of two lines
- Find the last Sunday of each month
- Find the missing permutation
- Find URI in text
- Finite state machine
- First class environments
- First-class functions
- First-class functions/Use numbers analogously
- Five weekends
- Fivenum
- Fixed length records
- FizzBuzz
- Flatten a list
- Flipping bits game
- Flow-control structures
- Floyd's triangle
- Floyd-Warshall algorithm
- Forest fire
- Fork
- Formal power series
- Formatted numeric output
- Forward difference
- Four bit adder
- Four is magic
- Four is the number of letters in the ...
- Fractal tree
- Fractran
- Free polyominoes enumeration
- French Republican calendar
- Function composition
- Function definition
- Function frequency
- Function prototype

### G

- Galton box animation
- Gamma function
- Gauss-Jordan matrix inversion
- Gaussian elimination
- General FizzBuzz
- Generalised floating point addition
- Generalised floating point multiplication
- Generate Chess960 starting position
- Generate lower case ASCII alphabet
- Generate random chess position
- Generator/Exponential
- Generic swap
- Globally replace text in several files
- Go Fish
- Gray code
- Grayscale image
- Greatest common divisor
- Greatest element of a list
- Greatest subsequential sum
- Greed
- Greyscale bars/Display
- Guess the number
- Guess the number/With feedback
- Guess the number/With feedback (player)
- GUI component interaction
- GUI enabling/disabling of controls
- GUI/Maximum window dimensions

### H

- Hailstone sequence
- Hamming numbers
- Handle a signal
- Happy numbers
- Harshad or Niven series
- Hash from two arrays
- Hash join
- Haversine formula
- Hello world/Graphical
- Hello world/Line printer
- Hello world/Newbie
- Hello world/Newline omission
- Hello world/Standard error
- Hello world/Text
- Here document
- Heronian triangles
- Hexapawn
- Hickerson series of almost integers
- Higher-order functions
- Hilbert curve
- History variables
- Hofstadter Figure-Figure sequences
- Hofstadter Q sequence
- Hofstadter-Conway $10,000 sequence
- Holidays related to Easter
- Honeycombs
- Horizontal sundial calculations
- Horner's rule for polynomial evaluation
- Host introspection
- Hough transform
- HTTP
- HTTPS
- HTTPS/Authenticated
- HTTPS/Client-authenticated
- Huffman coding
- Hunt The Wumpus

### I

- I before E except after C
- I'm a software engineer, get me out of here
- I.Q. Puzzle
- IBAN
- Identity matrix
- Idiomatically determine all the lowercase and uppercase letters
- Image noise
- Imaginary base numbers
- Implicit type conversion
- Include a file
- Increment a numerical string
- Index finite lists of positive integers
- Infinity
- Input loop
- Input/Output for Lines of Text
- Input/Output for Pairs of Numbers
- Integer comparison
- Integer overflow
- Integer roots
- Integer sequence
- Inverted index
- Iterated digits squaring

### K

- K-d tree
- K-means++ clustering
- Kahan summation
- Kaprekar numbers
- Kernighans large earthquake problem
- Keyboard input/Flush the keyboard buffer
- Keyboard input/Keypress check
- Keyboard input/Obtain a Y or N response
- Keyboard macros
- Knapsack problem/0-1
- Knapsack problem/Bounded
- Knapsack problem/Continuous
- Knapsack problem/Unbounded
- Knight's tour
- Knuth shuffle
- Knuth's algorithm S
- Knuth's power tree
- Koch curve
- Kolakoski sequence
- Kosaraju
- Kronecker product
- Kronecker product based fractals

### L

- Langton's ant
- Largest int from concatenated ints
- Largest number divisible by its digits
- Last Friday of each month
- Last letter-first letter
- Law of cosines - triples
- Leap year
- Least common multiple
- Left factorials
- Leonardo numbers
- Letter frequency
- Levenshtein distance
- Levenshtein distance/Alignment
- Linear congruential generator
- Linux CPU utilization
- List comprehensions
- Literals/Floating point
- Literals/Integer
- Literals/String
- Logical operations
- Long multiplication
- Long primes
- Longest common prefix
- Longest common subsequence
- Longest Common Substring
- Longest increasing subsequence
- Longest string challenge
- Look-and-say sequence
- Loop over multiple arrays simultaneously
- Loops/Break
- Loops/Continue
- Loops/Do-while
- Loops/Downward for
- Loops/For
- Loops/For with a specified step
- Loops/Foreach
- Loops/Increment loop index within loop body
- Loops/Infinite
- Loops/N plus one half
- Loops/Nested
- Loops/While
- Loops/with multiple ranges
- Loops/Wrong ranges
- LU decomposition
- Lucas-Lehmer test
- Lucky and even lucky numbers
- Ludic numbers
- Luhn test of credit card numbers
- Lychrel numbers
- LZW compression

### M

- Machine code
- Mad Libs
- Magic 8-Ball
- Magic squares of doubly even order
- Magic squares of odd order
- Magic squares of singly even order
- Main step of GOST 28147-89
- Make a backup file
- Make directory path
- Man or boy test
- Mandelbrot set
- Map range
- Markov chain text generator
- Matrix chain multiplication
- Matrix multiplication
- Matrix transposition
- Matrix-exponentiation operator
- Maximum triangle path sum
- Mayan numerals
- Maze generation
- Maze solving
- McNuggets Problem
- MD4
- MD5
- MD5/Implementation
- Median filter
- Memory allocation
- Memory layout of a data structure
- Menu
- Mersenne primes
- Metaprogramming
- Metered concurrency
- Metronome
- Middle three digits
- Miller–Rabin primality test
- Mind boggling card trick
- Minesweeper game
- Modular arithmetic
- Modular exponentiation
- Modular inverse
- Modulinos
- Monte Carlo methods
- Montgomery reduction
- Monty Hall problem
- Morse code
- Most frequent k chars distance
- Mouse position
- Move-to-front algorithm
- Multi-dimensional array
- Multifactorial
- Multiple distinct objects
- Multiple regression
- Multiplication tables
- Multiplicative order
- Multisplit
- Munchausen numbers
- Munching squares
- Musical scale
- Mutual recursion

### N

- N'th
- N-body problem
- N-queens problem
- Named parameters
- Names to numbers
- Naming conventions
- Narcissist
- Narcissistic decimal number
- Natural sorting
- Nautical bell
- Negative base numbers
- Nested function
- Nested templated data
- Non-continuous subsequences
- Non-decimal radices/Convert
- Non-decimal radices/Input
- Non-decimal radices/Output
- Nonoblock
- Nonogram solver
- Nth root
- Null object
- Number names
- Number reversal game
- Numeric error propagation
- Numerical and alphabetical suffixes
- Numerical integration
- Numerical integration/Adaptive Simpson's method
- Numerical integration/Gauss-Legendre Quadrature
- NYSIIS

### O

- Object serialization
- Odd word problem
- Old lady swallowed a fly
- Old Russian measure of length
- One of n lines in a file
- One-dimensional cellular automata
- One-time pad
- One-time pad/Phix
- OpenGL
- OpenGL/Utah Teapot
- Operator precedence
- Optional parameters
- Orbital elements
- Order disjoint list items
- Order two numerical lists
- Ordered Partitions
- Ordered words

### P

- P-value correction
- Palindrome detection
- Pangram checker
- Paraffins
- Parametric polymorphism
- Parametrized SQL statement
- Parse command-line arguments
- Parse EBNF
- Parsing/RPN calculator algorithm
- Parsing/RPN to infix conversion
- Parsing/Shunting-yard algorithm
- Partial function application
- Particle Swarm Optimization
- Partition an integer X into N primes
- Pascal matrix generation
- Pascal's triangle
- Pascal's triangle/Puzzle
- Password generator
- Pathological floating point problems
- Pattern matching
- Peaceful chess queen armies
- Peano curve
- Penney's game
- Penrose tiling
- Pentagram
- Pentomino tiling
- Percentage difference between images
- Perceptron
- Percolation/Bond percolation
- Percolation/Mean cluster density
- Percolation/Mean run density
- Percolation/Site percolation
- Perfect numbers
- Perfect shuffle
- Perfect totient numbers
- Perlin noise
- Permutation test
- Permutations
- Permutations by swapping
- Permutations with repetitions
- Permutations/Derangements
- Permutations/Rank of a permutation
- Pernicious numbers
- Phrase reversals
- Pi
- Pick random element
- Pig the dice game
- Pig the dice game/Player
- Pinstripe/Display
- Pinstripe/Printer
- Plasma effect
- Play recorded sounds
- Playfair cipher
- Playing cards
- Plot coordinate pairs
- Pointers and references
- Poker hand analyser
- Polymorphic copy
- Polymorphism
- Polynomial long division
- Polynomial regression
- Polynomial synthetic division
- Polyspiral
- Population count
- Power set
- Pragmatic directives
- Price fraction
- Primality by trial division
- Prime conspiracy
- Prime decomposition
- Primes - allocate descendants to their ancestors
- Primorial numbers
- Priority queue
- Probabilistic choice
- Problem of Apollonius
- Program name
- Program termination
- Proof
- Proper divisors
- Pythagoras tree
- Pythagorean quadruples
- Pythagorean triples

### R

- Railway circuit
- Ramer-Douglas-Peucker line simplification
- Ramsey's theorem
- Random number generator (device)
- Random number generator (included)
- Random numbers
- Range consolidation
- Range expansion
- Range extraction
- Ranking methods
- Rate counter
- Ray-casting algorithm
- RCRPG
- Read a configuration file
- Read a file character by character/UTF8
- Read a file line by line
- Read a specific line from a file
- Read entire file
- Readline interface
- Real constants and functions
- Recaman's sequence
- Reduced row echelon form
- Reflection/Get source
- Reflection/List methods
- Regular expressions
- Remove duplicate elements
- Remove lines from a file
- Rename a file
- Rendezvous
- Rep-string
- Repeat
- Repeat a string
- Resistor mesh
- Respond to an unknown method call
- Return multiple values
- Reverse a string
- Reverse the gender of a string
- Reverse words in a string
- RIPEMD-160
- Robots
- Robots/Phix
- Rock-paper-scissors
- Roman numerals/Decode
- Roman numerals/Encode
- Roots of a function
- Roots of a quadratic function
- Roots of unity
- Rosetta Code/Find unimplemented tasks
- Rosetta Code/Rank languages by number of users
- Rosetta Code/Rank languages by popularity
- Rosetta Code/Tasks without examples
- Rot-13
- RPG Attributes Generator
- RSA code
- Run-length encoding
- Runge-Kutta method

### S

- S-Expressions
- Safe addition
- Safe primes and unsafe primes
- Sailors, coconuts and a monkey problem
- Same Fringe
- Sattolo cycle
- Scope modifiers
- Scope/Function names and labels
- Search a list
- Search a list of records
- SEDOLs
- Selective File Copy
- Self-describing numbers
- Self-hosting compiler
- Self-referential sequence
- Semiprime
- Semordnilap
- Send an unknown method call
- Separate the house number from the street name
- Sequence of non-squares
- Sequence of primes by trial division
- Sequence of primorial primes
- Sequence: nth number with exactly n divisors
- Sequence: smallest number greater than previous term with exactly n divisors
- Sequence: smallest number with exactly n divisors
- Set
- Set consolidation
- Set of real numbers
- Set puzzle
- Seven-sided dice from five-sided dice
- Sexy primes
- SHA-1
- SHA-256
- Shoelace formula for polygonal area
- Short-circuit evaluation
- Shortest common supersequence
- Show Ascii table
- Show the epoch
- Sierpinski carpet
- Sierpinski triangle
- Sierpinski triangle/Graphical
- Sieve of Eratosthenes
- Simple database
- Simple windowed application
- Simulated annealing
- Sine wave
- Singly-linked list/Element definition
- Singly-linked list/Element insertion
- Singly-linked list/Element removal
- Singly-linked list/Traversal
- Sleep
- Smith numbers
- Snake
- Snake And Ladder
- Sokoban
- Solve a Hidato puzzle
- Solve a Holy Knight's tour
- Solve a Hopido puzzle
- Solve a Numbrix puzzle
- Solve a Rubik's Cube
- Solve the no connection puzzle
- Sort a list of object identifiers
- Sort an array of composite structures
- Sort an integer array
- Sort disjoint sublist
- Sort numbers lexicographically
- Sort stability
- Sort three variables
- Sort using a custom comparator
- Sorting algorithms/Bead sort
- Sorting algorithms/Bogosort
- Sorting algorithms/Bubble sort
- Sorting Algorithms/Circle Sort
- Sorting algorithms/Cocktail sort
- Sorting algorithms/Comb sort
- Sorting algorithms/Counting sort
- Sorting algorithms/Cycle sort
- Sorting algorithms/Gnome sort
- Sorting algorithms/Heapsort
- Sorting algorithms/Insertion sort
- Sorting algorithms/Merge sort
- Sorting algorithms/Pancake sort
- Sorting algorithms/Patience sort
- Sorting algorithms/Permutation sort
- Sorting algorithms/Quicksort
- Sorting algorithms/Radix sort
- Sorting algorithms/Selection sort
- Sorting algorithms/Shell sort
- Sorting algorithms/Sleep sort
- Sorting algorithms/Stooge sort
- Sorting algorithms/Strand sort
- Sorting algorithms/Tree sort on a linked list
- Soundex
- Sparkline in unicode
- Special characters
- Special variables
- Spelling of ordinal numbers
- Spinning rod animation/Text
- Spiral matrix
- Split a character string based on change of character
- Spoof game
- Square but not cube
- Square-free integers
- Stable marriage problem
- Stack
- Stack traces
- Stair-climbing puzzle
- Start from a main routine
- Starting a web browser
- State name puzzle
- Statistics/Basic
- Statistics/Normal distribution
- Stem-and-leaf plot
- Stern-Brocot sequence
- Straddling checkerboard
- Stream Merge
- String append
- String case
- String comparison
- String concatenation
- String interpolation (included)
- String length
- String matching
- String prepend
- Strip a set of characters from a string
- Strip block comments
- Strip comments from a string
- Strip control codes and extended characters from a string
- Strip whitespace from a string/Top and tail
- Strong and weak primes
- Subleq
- Subset sum problem
- Substitution Cipher
- Substring
- Substring/Top and tail
- Subtractive generator
- Successive prime differences
- Sudoku
- Suffix tree
- Suffixation of decimal numbers
- Sum and product of an array
- Sum and Product Puzzle
- Sum digits of an integer
- Sum multiples of 3 and 5
- Sum of a series
- Sum of squares
- Sum to 100
- Sunflower fractal
- Superellipse
- Superpermutation minimisation
- Sutherland-Hodgman polygon clipping
- Symmetric difference
- Synchronous concurrency
- System time

### T

- Table creation
- Table creation/Postal addresses
- Take notes on the command line
- Tarjan
- Taxicab numbers
- Temperature conversion
- Terminal control/Clear the screen
- Terminal control/Coloured text
- Terminal control/Cursor movement
- Terminal control/Cursor positioning
- Terminal control/Dimensions
- Terminal control/Display an extended character
- Terminal control/Hiding the cursor
- Terminal control/Inverse video
- Terminal control/Positional read
- Terminal control/Preserve screen
- Terminal control/Restricted width positional input/No wrapping
- Terminal control/Restricted width positional input/With wrapping
- Terminal control/Ringing the terminal bell
- Terminal control/Unicode output
- Ternary logic
- Test integerness
- Text between
- Text processing/1
- Text processing/2
- Text processing/Max licenses in use
- Text to HTML
- Textonyms
- The ISAAC Cipher
- The Name Game
- The Twelve Days of Christmas
- Thiele's interpolation formula
- Thue-Morse
- Tic-tac-toe
- Time a function
- Tokenize a string
- Tokenize a string with escaping
- Tonelli-Shanks algorithm
- Top rank per group
- Topic variable
- Topological sort
- Topological sort/Extracted top item
- Topswops
- Total circles area
- Totient function
- Towers of Hanoi
- Trabb Pardo–Knuth algorithm
- Transportation problem
- Tree traversal
- Trigonometric functions
- Truncatable primes
- Truncate a file
- Truth table
- Twelve statements
- Two Sum
- Type detection

### U

- Ulam spiral (for primes)
- Unbias a random generator
- Undefined values
- Unicode polynomial equation
- Unicode strings
- Unicode variable names
- Universal Turing machine
- Unix/ls
- Update a configuration file
- URL decoding
- URL encoding
- URL parser
- Use another language to call a function
- User input/Graphical
- User input/Text
- UTF-8 encode and decode

### V

- Validate International Securities Identification Number
- Vampire number
- Van der Corput sequence
- Variable size/Get
- Variable size/Set
- Variable-length quantity
- Variables
- Variadic function
- Vector
- Vector products
- Verify distribution uniformity/Chi-squared test
- Verify distribution uniformity/Naive
- Vibrating rectangles
- Video display modes
- Vigenère cipher
- Vigenère cipher/Cryptanalysis
- Visualize a tree
- VList
- Vogel's approximation method
- Voronoi diagram

### W

- Walk a directory/Non-recursively
- Walk a directory/Recursively
- Water collected between towers
- Web scraping
- Weird numbers
- Welch's t-test
- Window creation
- Window management
- Wireworld
- Word break problem
- Word count
- Word search
- Word wrap
- World Cup group stage
- Write entire file
- Write float arrays to a text file
- Write language name in 3D ASCII