/*
PSPP - a program for statistical analysis.
Copyright (C) 2017 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see .
*/
#ifndef ALGORITHM_H
#define ALGORITHM_H 1
#include
#include
/* Compares A and B, given auxiliary data AUX, and returns a
strcmp()-type result. */
typedef int algo_compare_func (const void *a, const void *b, const void *aux);
/* Tests a predicate on DATA, given auxiliary data AUX */
typedef bool algo_predicate_func (const void *data, const void *aux);
/* Returns a random number in the range 0 through MAX exclusive,
given auxiliary data AUX. */
typedef unsigned algo_random_func (unsigned max, const void *aux);
/* A generally suitable random function. */
algo_random_func algo_default_random;
/* Finds an element in ARRAY, which contains COUNT elements of
SIZE bytes each, using COMPARE for comparisons. Returns the
first element in ARRAY that matches TARGET, or a null pointer
on failure. AUX is passed to each comparison as auxiliary
data. */
void *find (const void *array, size_t count, size_t size,
const void *target,
algo_compare_func *compare, const void *aux);
/* Counts and return the number of elements in ARRAY, which
contains COUNT elements of SIZE bytes each, which are equal to
ELEMENT as compared with COMPARE. AUX is passed as auxiliary
data to COMPARE. */
size_t count_equal (const void *array, size_t count, size_t size,
const void *element,
algo_compare_func *compare, const void *aux);
/* Counts and return the number of elements in ARRAY, which
contains COUNT elements of SIZE bytes each, for which
PREDICATE returns true. AUX is passed as auxiliary data to
PREDICATE. */
size_t count_if (const void *array, size_t count, size_t size,
algo_predicate_func *predicate, const void *aux);
/* Sorts ARRAY, which contains COUNT elements of SIZE bytes each,
using COMPARE for comparisons. AUX is passed to each
comparison as auxiliary data. */
void sort (void *array, size_t count, size_t size,
algo_compare_func *compare, const void *aux);
/* Tests whether ARRAY, which contains COUNT elements of SIZE
bytes each, is sorted in order according to COMPARE. AUX is
passed to COMPARE as auxiliary data. */
bool is_sorted (const void *array, size_t count, size_t size,
algo_compare_func *compare, const void *aux);
/* Makes the elements in ARRAY unique, by moving up duplicates,
and returns the new number of elements in the array. Sorted
arrays only. Arguments same as for sort() above. */
size_t unique (void *array, size_t count, size_t size,
algo_compare_func *compare, const void *aux);
/* Helper function that calls sort(), then unique(). */
size_t sort_unique (void *array, size_t count, size_t size,
algo_compare_func *compare, const void *aux);
/* Reorders ARRAY, which contains COUNT elements of SIZE bytes
each, so that the elements for which PREDICATE returns true
precede those for which PREDICATE returns false. AUX is passed
as auxiliary data to PREDICATE. Returns the number of
elements for which PREDICATE returns true. Not stable. */
size_t partition (void *array, size_t count, size_t size,
algo_predicate_func *predicate, const void *aux);
/* Checks whether ARRAY, which contains COUNT elements of SIZE
bytes each, is partitioned such that PREDICATE returns true
for the first TRUE_CNT elements and zero for the remaining
elements. AUX is passed as auxiliary data to PREDICATE. */
bool is_partitioned (const void *array, size_t count, size_t size,
size_t n_trues,
algo_predicate_func *predicate, const void *aux);
/* Randomly reorders ARRAY, which contains COUNT elements of SIZE
bytes each. Uses RANDOM as a source of random data, passing
AUX as the auxiliary data. RANDOM may be null to use a
default random source. */
void random_shuffle (void *array, size_t count, size_t size,
algo_random_func *random, const void *aux);
/* Copies the COUNT elements of SIZE bytes each from ARRAY to
RESULT, except that elements for which PREDICATE is false are
not copied. Returns the number of elements copied. AUX is
passed to PREDICATE as auxiliary data. */
size_t copy_if (const void *array, size_t count, size_t size,
void *result,
algo_predicate_func *predicate, const void *aux);
/* Removes N elements starting at IDX from ARRAY, which consists
of COUNT elements of SIZE bytes each, by shifting the elements
following them, if any, into its position. */
void remove_range (void *array, size_t count, size_t size,
size_t idx, size_t n);
/* Removes element IDX from ARRAY, which consists of COUNT
elements of SIZE bytes each, by shifting the elements
following it, if any, into its position. */
void remove_element (void *array, size_t count, size_t size,
size_t idx);
/* Makes room for N elements starting at IDX in ARRAY, which
initially consists of COUNT elements of SIZE bytes each, by
shifting elements IDX...COUNT (exclusive) to the right by N
positions. */
void insert_range (void *array, size_t count, size_t size,
size_t idx, size_t n);
/* Makes room for a new element at IDX in ARRAY, which initially
consists of COUNT elements of SIZE bytes each, by shifting
elements IDX...COUNT (exclusive) to the right by one
position. */
void insert_element (void *array, size_t count, size_t size,
size_t idx);
/* Moves an element in ARRAY, which consists of COUNT elements of
SIZE bytes each, from OLD_IDX to NEW_IDX, shifting around
other elements as needed. Runs in O(abs(OLD_IDX - NEW_IDX))
time. */
void move_element (void *array, size_t count, size_t size,
size_t old_idx, size_t new_idx);
/* Moves N elements in ARRAY starting at OLD_IDX, which consists
of COUNT elements of SIZE bytes each, so that they now start
at NEW_IDX, shifting around other elements as needed. */
void move_range (void *array, size_t count, size_t size,
size_t old_idx, size_t new_idx, size_t n);
/* Removes elements equal to ELEMENT from ARRAY, which consists
of COUNT elements of SIZE bytes each. Returns the number of
remaining elements. AUX is passed to COMPARE as auxiliary
data. */
size_t remove_equal (void *array, size_t count, size_t size,
void *element,
algo_compare_func *compare, const void *aux);
/* Copies the COUNT elements of SIZE bytes each from ARRAY to
RESULT, except that elements for which PREDICATE is true are
not copied. Returns the number of elements copied. AUX is
passed to PREDICATE as auxiliary data. */
size_t remove_copy_if (const void *array, size_t count, size_t size,
void *result,
algo_predicate_func *predicate, const void *aux);
/* Searches ARRAY, which contains COUNT elements of SIZE bytes
each, for VALUE, using a binary search. ARRAY must ordered
according to COMPARE. AUX is passed to COMPARE as auxiliary
data. */
void *binary_search (const void *array, size_t count, size_t size,
void *value,
algo_compare_func *compare, const void *aux);
/* Lexicographically compares ARRAY1, which contains COUNT1
elements of SIZE bytes each, to ARRAY2, which contains COUNT2
elements of SIZE bytes, according to COMPARE. Returns a
strcmp()-type result. AUX is passed to COMPARE as auxiliary
data. */
int lexicographical_compare_3way (const void *array1, size_t count1,
const void *array2, size_t count2,
size_t size,
algo_compare_func *compare, const void *aux);
/* Computes the generalized set difference, ARRAY1 minus ARRAY2,
into RESULT, and returns the number of elements written to
RESULT. If a value appears M times in ARRAY1 and N times in
ARRAY2, then it will appear max(M - N, 0) in RESULT. ARRAY1
and ARRAY2 must be sorted, and RESULT is sorted and stable.
ARRAY1 consists of COUNT1 elements, ARRAY2 of COUNT2 elements,
each SIZE bytes. AUX is passed to COMPARE as auxiliary
data. */
size_t set_difference (const void *array1, size_t count1,
const void *array2, size_t count2,
size_t size,
void *result,
algo_compare_func *compare, const void *aux);
/* Finds the first pair of adjacent equal elements in ARRAY,
which has COUNT elements of SIZE bytes. Returns the first
element in ARRAY such that COMPARE returns true when it and
its successor element are compared. AUX is passed to COMPARE
as auxiliary data. */
void *adjacent_find_equal (const void *array, size_t count, size_t size,
algo_compare_func *compare, const void *aux);
/* ARRAY contains COUNT elements of SIZE bytes each. Initially
the first COUNT - 1 elements of these form a heap, followed by
a single element not part of the heap. This function adds the
final element, forming a heap of COUNT elements in ARRAY.
Uses COMPARE to compare elements, passing AUX as auxiliary
data. */
void push_heap (void *array, size_t count, size_t size,
algo_compare_func *compare, const void *aux);
/* ARRAY contains COUNT elements of SIZE bytes each. Initially
all COUNT elements form a heap. This function moves the
largest element in the heap to the final position in ARRAY and
reforms a heap of the remaining COUNT - 1 elements at the
beginning of ARRAY. Uses COMPARE to compare elements, passing
AUX as auxiliary data. */
void pop_heap (void *array, size_t count, size_t size,
algo_compare_func *compare, const void *aux);
/* Turns ARRAY, which contains COUNT elements of SIZE bytes, into
a heap. Uses COMPARE to compare elements, passing AUX as
auxiliary data. */
void make_heap (void *array, size_t count, size_t size,
algo_compare_func *compare, const void *aux);
/* ARRAY contains COUNT elements of SIZE bytes each. Initially
all COUNT elements form a heap. This function turns the heap
into a fully sorted array. Uses COMPARE to compare elements,
passing AUX as auxiliary data. */
void sort_heap (void *array, size_t count, size_t size,
algo_compare_func *compare, const void *aux);
/* ARRAY contains COUNT elements of SIZE bytes each. This
function tests whether ARRAY is a heap and returns true if so,
false otherwise. Uses COMPARE to compare elements, passing
AUX as auxiliary data. */
bool is_heap (const void *array, size_t count, size_t size,
algo_compare_func *compare, const void *aux);
/* Reverses the order of ARRAY, which contains COUNT elements of SIZE bytes
each. */
void reverse_array (void *array, size_t count, size_t size);
#endif /* algorithm.h */