blob: a9ab28b43aa5f50c2ab4433e483d7540c957124e (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
|
#include "loans.h"
contract *mort_init(int n, int d, double r, double P) {
if ((n < 0)) return NULL;
if ((d >= n)||(d < 0)) return NULL;
contract *c = (contract *)calloc(1, sizeof(contract));
c->n = (unsigned int)n;
c->d = (unsigned int)d;
c->r = r;
c->P = P;
return c;
}
double mort_update(contract *c) {
if (c->k > c->n)
return 0.0;
if (c->k == c->d) {
c->A = - (c->P * c->r * pow(1.0 + c->r, (double)(c->n - c->k)));
c->A = c->A / (1.0 - pow(1.0 + c->r, (double)(c->n - c->k)));
}
c->k++;
c->I = c->r * c->P;
if (c->k <= c->d)
c->P += c->I;
else {
c->D = c->A - c->I;
c->P = c->P - c->D;
/* c->A is fixed ! */
}
return c->A;
}
void mort_free(contract *c) {
free(c);
}
|
