Identity function
An identity function is a function that maps every input to itself unchanged.
Sutskever's List
- How it is used
- Explains how residual shortcuts let added layers preserve an input when no useful transformation is learned.
- How deep it goes
- Defines identity through unchanged input and explains block-level consequences; stops short of a formal derivation.
- Examples
- Uses plain-network depth comparisons, a two-path ResNet block, and ablations that alter the shortcut.
- What you can do after
- Evaluate/understand why an unaltered shortcut helps deep residual networks train and why post-addition operations can interfere.
Functional Programming in JavaScript
A function that returns its argument unchanged.
- How it is used
- Supplies unchanged values to higher-order functions and helps test or connect functional combinators.
- How deep it goes
- Defines the unchanged return behavior and lists practical uses without developing an implementation or mathematical treatment.
- Examples
- Uses the identity signature, point-free function arguments, combinator unit tests, and functional data extraction as examples.
- What you can do after
- Apply it as a neutral function argument and use it to test functional composition or combinator flow.
Read how Functional Programming in JavaScript explains identity function →
Fabulous Adventures in Data Structures and Algorithms
An identity function returns its argument unchanged.
- How it is used
- Uses the identity function to represent the empty Hughes list and preserve concatenation behavior.
- How deep it goes
- Defines the function algebraically and implements it as a C# delegate, including reference-identity handling.
- Examples
- Demonstrates captured integer storage and an empty Hughes list implemented by a delegate returning its stack argument.
- What you can do after
- Apply it via C# delegates to model empty Hughes lists and compose stack-preserving concatenations.
Read how Fabulous Adventures in Data Structures and Algorithms explains identity function →
Related concepts
- partition-byused by · partition-by is a Clojure function that partitions a sequence whenever successive results of a function differ.
- traverseuses · Traverse is an operation that maps an effectful function across a traversable structure and collects the results within an applicative context.
- functionkind of · A function is a callable program unit that performs an operation, may accept inputs, and can produce a result or side effect.
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