std_algorithm_status.md

OpenSCAD Algorithm Implementation Status (C++ STL based)

List of STL Algorithms pulled from cppreference.com

Key

Status	Description
✔️	DONE
✅	TODO
❌#	Not Applicable to OpenSCAD (with numbered note)
❓#	Unsure if applicable (with numbered note)
➕	Bonus Implemented in std library style, but not a native STL function

Non-modifying sequence operations

Status	Function Name	Description
➕	end	returns last or len(v) if last undefined, similar to container::end() iterator.
✔️	all_of	checks if a predicate is true for all of the elements in a range
✔️	any_of	checks if a predicate is true for any of the elements in a range
✔️	none_of	checks if a predicate is true for none of the elements in a range
✔️	for_each
✔️	for_each_n	applies a function object to the first n elements of a sequence
✔️	count
✔️	count_if	returns the number of elements satisfying specific criteria
✔️	mismatch	finds the first position where two ranges differ
✔️	find
✔️	find_if
✔️	find_if_not	finds the first element satisfying specific criteria
➕	contains	like find, but return boolean instead of index
✔️	find_end	finds the last sequence of elements in a certain range
✔️	find_first_of	searches for any one of a set of elements
✔️	adjacent_find	finds the first two adjacent items that are equal (or satisfy a given predicate)
✔️	search	searches for a range of elements
✔️	search_n	searches a range for a number of consecutive copies of an element

Modifying sequence operations

Status	Function Name	Description
✔️	copy
✔️	copy_if	copies a range of elements to a new location
✔️	copy_n	copies a number of elements to a new location
✔️	copy_backward	copies a range of elements in backwards order
❌1	move	moves a range of elements to a new location
❌1	move_backward	moves a range of elements to a new location in backwards order
✔️	fill	copy-assigns the given value to every element in a range
✔️	fill_n	copy-assigns the given value to N elements in a range
✔️	transform	applies a function to a range of elements, storing results in a destination range
➕	transform2	applies a function to a range of elements, storing results in a destination range
✔️	generate	assigns the results of successive function calls to every element in a range
✔️	generate_n	assigns the results of successive function calls to N elements in a range
✔️	remove
✔️	remove_if	removes elements satisfying specific criteria
✔️	remove_copy
✔️	remove_copy_if	copies a range of elements omitting those that satisfy specific criteria
✔️	replace
✔️	replace_if	replaces all values satisfying specific criteria with another value
✔️	replace_copy
✔️	replace_copy_if	copies a range, replacing elements satisfying specific criteria with another value
❌	swap	swaps the values of two objects
✔️	swap_ranges	swaps two ranges of elements
✔️	iter_swap	swaps the elements pointed to by two iterators
✔️	reverse	reverses the order of elements in a range
✔️	reverse_copy	creates a copy of a range that is reversed
✔️	rotate	rotates the order of elements in a range
✔️	rotate_copy	copies and rotate a range of elements
❓	shift_left
❓	shift_right	shifts elements in a range
❌	random_shuffle
✅	shuffle	randomly re-orders elements in a range
✅	sample	selects n random elements from a sequence
✔️	unique	removes consecutive duplicate elements in a range
✅	unique_copy	creates a copy of some range of elements that contains no consecutive duplicates

Partitioning operations

Status	Function Name	Description
✅	is_partitioned	determines if the range is partitioned by the given predicate
❌2	partition	divides a range of elements into two groups
✅	partition_copy	copies a range dividing the elements into two groups
✔️	stable_partition	divides elements into two groups while preserving their relative order
✅	partition_point	locates the partition point of a partitioned range

Sorting operations

Status	Function Name	Description
✅	is_sorted	checks whether a range is sorted into ascending order
✅	is_sorted_until	finds the largest sorted subrange
✅	sort	sorts a range into ascending order
✅	partial_sort	sorts the first N elements of a range
✅	partial_sort_copy	copies and partially sorts a range of elements
❓2	stable_sort	sorts a range of elements while preserving order between equal elements
✅	nth_element	partially sorts the given range making sure that it is partitioned by the given element

Binary search operations (on sorted ranges)

Status	Function Name	Description
✔️	lower_bound	returns an iterator to the first element not less than the given value
✔️	upper_bound	returns an iterator to the first element greater than a certain value
✔️	binary_search	determines if an element exists in a certain range
✅	equal_range	returns range of elements matching a specific key

Other operations on sorted ranges

Status	Function Name	Description
✅	merge	merges two sorted ranges
❓1	inplace_merge	merges two ordered ranges in-place

Set operations (on sorted ranges)

Status	Function Name	Description
✅	includes	returns true if one set is a subset of another
✅	set_difference	computes the difference between two sets
✅	set_intersection	computes the intersection of two sets
✅	set_symmetric_difference	computes the symmetric difference between two sets
✅	set_union	computes the union of two sets

Heap operations

Status	Function Name	Description
❓3	is_heap	checks if the given range is a max heap
❓3	is_heap_until	finds the largest subrange that is a max heap
❓3	make_heap	creates a max heap out of a range of elements
❓3	push_heap	adds an element to a max heap
❓3	pop_heap	removes the largest element from a max heap
❓3	sort_heap	turns a max heap into a range of elements sorted in ascending order

Minimum/maximum operations

Status	Function Name	Description
✔️	max	returns the greater of the given values
✔️	max_element	returns the largest element in a range
✔️	min	returns the smaller of the given values
✔️	min_element	returns the smallest element in a range
✔️	minmax	returns the smaller and larger of two elements
✔️	minmax_element	returns the smallest and the largest elements in a range
✔️	clamp	clamps a value between a pair of boundary values

Comparison operations

Status	Function Name	Description
✅	equal	determines if two sets of elements are the same
✅	lexicographical_compare	returns true if one range is lexicographically less than another
✅	lexicographical_compare_three_way	compares two ranges using three-way comparison

Permutation operations

Status	Function Name	Description
✅	is_permutation	determines if a sequence is a permutation of another sequence
✅	next_permutation	generates the next greater lexicographic permutation of a range of elements
✅	prev_permutation	generates the next smaller lexicographic permutation of a range of elements

Numeric operations

Status	Function Name	Description
✅	iota	fills a range with successive increments of the starting value
✔️	accumulate	sums up a range of elements
✅	inner_product	computes the inner product of two ranges of elements
✅	adjacent_difference	computes the differences between adjacent elements in a range
✅	partial_sum	computes the partial sum of a range of elements
❌4	reduce	similar to std::accumulate, except out of order
✅	exclusive_scan	similar to std::partial_sum, excludes the ith input element from the ith sum
✅	inclusive_scan	similar to std::partial_sum, includes the ith input element in the ith sum
✅	transform_reduce	applies a functor, then reduces out of order
✅	transform_exclusive_scan	applies a functor, then calculates exclusive scan
✅	transform_inclusive_scan	applies a functor, then calculates inclusive scan

Operations on uninitialized memory

Status	Function Name	Description
❌5	uninitialized_copy	copies a range of objects to an uninitialized area of memory
❌5	uninitialized_copy_n	copies a number of objects to an uninitialized area of memory
❌5	uninitialized_fill	copies an object to an uninitialized area of memory, defined by a range
❌5	uninitialized_fill_n	copies an object to an uninitialized area of memory, defined by a start and a count
❌5	uninitialized_move	moves a range of objects to an uninitialized area of memory
❌5	uninitialized_move_n	moves a number of objects to an uninitialized area of memory
❌5	uninitialized_default_construct	constructs objects by default-initialization in an uninitialized area of memory, defined by a range
❌5	uninitialized_default_construct_n	constructs objects by default-initialization in an uninitialized area of memory, defined by a start and a count
❌5	uninitialized_value_construct	constructs objects by value-initialization in an uninitialized area of memory, defined by a range
❌5	uninitialized_value_construct_n	constructs objects by value-initialization in an uninitialized area of memory, defined by a start and a count
❌5	destroy_at	destroys an object at a given address
❌5	destroy	destroys a range of objects
❌5	destroy_n	destroys a number of objects in a range

C library

Status	Function Name	Description
❓6	qsort	sorts a range of elements with unspecified type
❓7	bsearch	searches an array for an element of unspecified type

Totals:

Count	Type
52	DONE
34	TODO
19	Not Applicable
12	Unsure
117	Total STL algos
3	Bonus

Notes

1. OpenSCAD doesn't differentiate between copy and move (everything is copy due to immutability)

2. Don't think there is a way to benefit from unstable version in OpenSCAD so "stable_" is already implied

3. Not sure if heap type operations can be implemented in such a way that is efficient/worth using?

4. Don't think there would be any difference between reduce and accumulate for OpenSCAD. Choose one name?

   Also, fold exists under "Common higher-order function" (not STL based), but might want to call that reduce?

5. No low-level memory management in OpenSCAD

6. Don't think we can do quicksort efficiently since every swap requires a whole new list (mergesort makes most sense?)

7. Don't think there'd be any significant difference between bsearch and binary_search given that we just use indices not iterators or pointers