void entry_remove(entry_t **list, char *name)
{
entry_t *previous = NULL, *iterator = NULL;
if (name == NULL)
return;
iterator = *list;
while (iterator != NULL)
{
if (iterator->type == POLYNOMIAL && !strcmp(name, ((polynomial_t*) iterator->polynomial)->name))
break;
else if (iterator->type == POLYMORPH && !strcmp(name, ((polymorph_t*) iterator->polynomial)->name))
break;
previous = iterator;
iterator = iterator->next;
}
if (previous == NULL)
*list = iterator->next;
else
previous->next = iterator->next;
if (iterator->type == POLYNOMIAL)
polynomial_free((polynomial_t*) iterator->polynomial);
else if (iterator->type == POLYMORPH)
polymorph_free((polymorph_t*) iterator->polynomial);
else
free(iterator->polynomial);
free(iterator);
}
void entry_add(entry_t **list, void *polynomial, unsigned char type)
{
entry_t *iterator = NULL, *previous = NULL;
if (polynomial == NULL)
return;
if (*list == NULL)
{
*list = (entry_t*) malloc(sizeof(entry_t));
if (*list == NULL)
return;
(*list)->polynomial = polynomial;
(*list)->type = type;
(*list)->next = NULL;
}
else
{
previous = NULL;
iterator = *list;
while (iterator != NULL)
{
if (type == POLYNOMIAL && !strcmp(((polynomial_t*) iterator->polynomial)->name, ((polynomial_t*) polynomial)->name))
break;
else if (type == POLYMORPH && !strcmp(((polymorph_t*) iterator->polynomial)->name, ((polymorph_t*) polynomial)->name))
break;
previous = iterator;
iterator = iterator->next;
}
if (iterator != NULL)
{
if (iterator->type == POLYNOMIAL)
polynomial_free((polynomial_t*) iterator->polynomial);
else if (iterator->type == POLYMORPH)
polymorph_free((polymorph_t*) iterator->polynomial);
iterator->polynomial = polynomial;
}
else
{
previous->next = (entry_t*) malloc(sizeof(entry_t));
if (previous->next == NULL)
return;
previous->next->polynomial = polynomial;
previous->next->type = type;
previous->next->next = NULL;
}
}
}
polynomial_t *polynomial_extract(polynomial_t *p, unsigned long degree, unsigned long end)
{
polynomial_t *q = NULL;
complex_t *z = NULL;
monomial_t *iterator = NULL;
unsigned long i = 0;
if (p == NULL)
return NULL;
q = polynomial_init(NULL);
if (q == NULL)
return NULL;
for (i = p->degree, iterator = p->first; i >= end && iterator != NULL; i--, iterator = iterator->next)
{
if (degree >= iterator->degree && iterator->degree >= end)
{
z = complex_init(iterator->coef->re, iterator->coef->im);
if (z == NULL)
{
polynomial_free(q);
return NULL;
}
polynomial_append(q, z, iterator->degree);
}
}
if (q->size == 0)
{
polynomial_free(q);
q = NULL;
}
return q;
}
Polynomial* polynomial_power(const Polynomial *polynomial, int power) {
assert(polynomial != NULL);
assert(power > 0);
Polynomial *result = polynomial_copy(polynomial);
while(power > 1) {
Polynomial *tmp = result;
result = polynomial_product(result, polynomial);
if(tmp != polynomial) {
polynomial_free(&tmp);
}
power--;
}
return result;
}
void entry_free(entry_t **list)
{
entry_t *next = NULL;
if (*list == NULL)
return;
while (*list != NULL)
{
next = (*list)->next;
if ((*list)->type == POLYNOMIAL)
polynomial_free((polynomial_t*) (*list)->polynomial);
else if ((*list)->type == POLYMORPH)
polymorph_free((polymorph_t*) (*list)->polynomial);
else
free((*list)->polynomial);
free(*list);
*list = next;
}
}
Polynomial* polynomial_create_from_string(char *string) {
assert(string != NULL);
// read a random number of numbers
// example string: 7x^3 + x^2 -9x + 30
// allowed characters: digits, +, -, x, ^
Polynomial* new_polynomial = polynomial_create_empty();
Monomial* previous_monomial = NULL;
char *cursor = string;
long max_monomial_degree = 0;
int first_monomial = 1;
while(*cursor != '\0') {
monomials_errno = MONOMIAL_SUCCESS;
char *tmp_cursor = cursor;
Monomial *new_monomial = monomial_create_from_string(cursor, &tmp_cursor);
switch(monomials_errno) {
case MONOMIAL_INPUT_ERROR:
fprintf(stderr, "Fatal error: malformatted input!\nExiting\n");
exit(EXIT_FAILURE);
default: break;
}
cursor = tmp_cursor;
long new_degree = monomial_get_degree(new_monomial);
if(max_monomial_degree < new_degree) {
max_monomial_degree = new_degree;
}
if(first_monomial) {
new_polynomial->first = new_monomial;
first_monomial = 0;
} else {
monomial_set_next(previous_monomial, new_monomial);
}
previous_monomial = new_monomial;
// skip spaces
while(*cursor == ' ') {
cursor++;
}
}
new_polynomial->degree = max_monomial_degree;
// remove null monomials which may be there (e.g. 0x^12)
polynomial_remove_null_monomials(new_polynomial);
if(!new_polynomial->first) {
// empty polynomial
polynomial_free(&new_polynomial);
return NULL;
}
// reduct the polynomial (e.g. in case the user has input 2x - 6x)
Polynomial *reducted = polynomial_reduct(new_polynomial);
polynomial_free(&new_polynomial);
if(!reducted->first) {
// empty polynomial
polynomial_free(&reducted);
return NULL;
}
return reducted;
}
