jane@tolerant.UUCP (Jane Medefesser) (09/25/88)
Posting-number: Volume 4, Issue 90
Submitted-by: "Jane Medefesser" <jane@tolerant.UUCP>
Archive-name: loan
I have been using this program for years (at least 4!! :-) )
When we bought our house, it calculated the payment EXACTLY
as the bank did. Currently set up to compile on BSD and SysV -
pretty straight forward stuff...
====
hit return to continue
============================================================================
/*
*
* loan.c
* @(#) loan.c amoritization program
*
* acronym: loan amortization program
* ----
*
* purpose: calculates monthly payment, future value
* and creates an amortization schedule
*
* 06/27/84 Bill Gregg, Informatics General Corp.
* 07/12/84 Revision 1
* 07/12/84 Revision 2
* 11/05/85 Jane Medefesser, Implementation NPSN Unix (wilbur)
* compile as follows: 'cc -o <outfile> loan.c -lm'
* 12/05/85 Changes to direct output to a file.
* 03/02/88 Implemented on Eternity 5.3.1
*
*/
#include <stdio.h>
#include <math.h>
/*
*
*/
main() /* loan program */
{
float amt, term, rate, ic;
float r, temp, pmt, fv;
float exp, prin, x, y, mbeg, mnbr, yrint = 0;
int month, i, k, a = 0, yr=1;
char d, filename[9], c;
FILE *fp;
/* prompt for input from terminal */
printf("Enter principal amount: ");
scanf("%f", &amt);
printf("Enter term in years: ");
scanf("%f", &term);
printf("Enter interest rate in percent: ");
scanf("%f", &rate);
printf("Enter month payments begin (ex: 8 = August): ");
scanf("%f", &mbeg);
/* compute payment and future value */
r = rate/100.0;
x = 1.0 + r/12.0;
y = term*12.0;
temp = (1.0 / pow(x,y));
pmt = (amt*r/12.0) / (1-temp);
k = term*12;
fv = pmt*k;
ic = fv - amt;
printf("Do you want the report directed to a file or to the screen?");
printf("\n[f = file / s = screen] : ");
d = getchar(); /* This is only here to eat up the '\n' left over
from the last scanf. */
d = getchar();
switch(d) {
case 'f':
d = getchar();
printf("\nEnter a filename: ");
scanf("%s", filename);
while((c = getchar()) != '\n') {
filename[a] = c; a++; }
fp = fopen(filename, "w");
break;
default:
fp = stdout;
break;
}
/* print header */
fprintf(fp,"\n\t *** Amortization Schedule ***\n\n");
fprintf(fp,"Principal: %.2f\n", amt);
fprintf(fp,"Future value: %.2f\n", fv);
fprintf(fp,"Term of loan in years: %.1f\n", term);
fprintf(fp,"Interest Rate: %3.3f\n", rate);
fprintf(fp,"Total Interest Charge: %.2f\n", ic);
fprintf(fp,"Payment: %.2f\n", pmt);
fprintf(fp,"\nMONTH\tPRINCIPAL\tINTEREST\tBALANCE\n");
/* start of loop to print amortization schedule */
mnbr=mbeg;
for (i=1; i<=k; i++) {
month = i;
exp = amt*(r/12.0);
yrint=yrint+exp;
prin = pmt-exp;
amt = amt-prin;
mnbr++;
fprintf(fp,"%d\t %.2f\t\t %.2f\t\t %.2f\n", month, prin, exp, amt);
if (mnbr > 12 ) {
fprintf(fp,"\t\tInterest paid for year %d is %.2f\n\n",yr,yrint);
yr++;
yrint=0;
mnbr=1;
}
}
fprintf(fp,"\t\tInterest paid for year %d is %.2f\n\n",yr,yrint);
fclose(fp);
}