sparks@corpane.UUCP (John Sparks) (08/16/89)
Here is a newer version of the mortgage calculator program that was posted here
a while back. I added a way to keep track of additional principal paid, and I
reformatted the output to give more useful information, including keeping track
of total interest, and principal on a month to month and yearly basis.
It's still not perfect. I haven't added much error trapping or anything. If you
enter nothing when asked for a number, it might crash. I never bothered to fix
that. But I thought maybe some of you out there might want it, anyway.
Here it is:
-----------------8<----------------------------------------------
echo x - mort.c
sed 's/^X//' >mort.c <<'*-*-END-of-mort.c-*-*'
X/*
X *
X * loan.c
X * @(#) loan.c amoritization program
X * downloaded from usenet and modified by John Sparks
X * added: principal payments, reformatted output.
X *
X * compile with: cc -O mort.c -o mort -lm
X */
X
X#include <stdio.h>
X#include <math.h>
X
X/*
X *
X */
X
Xmain() /* loan program */
X{
X float amt, term, rate, ic;
X float r, temp, pmt, prpmt, fv;
X float exp, prin, x, y, mbeg, mnbr, yrint = 0;
X float yrprin = 0, acprin = 0, acint = 0, actotal = 0;
X int month, i, k, a = 0, yr=1;
X char d, filename[9], c;
X FILE *fp;
X /* prompt for input from terminal */
X printf(" This Program is provided for your personal information
only.\n");
X printf(" DISK claims no responsibility as to the accuracy");
X printf(" of the data provided.\n\n");
X
X printf("Enter principal amount: ");
X scanf("%f", &amt);
X
X printf("Enter term in years: ");
X scanf("%f", &term);
X
X printf("Enter interest rate in percent (ex: 10 = 10 percent): ");
X scanf("%f", &rate);
X
X
X printf("Enter additional Principal payment (Enter 0 if none): ");
X scanf("%f", &prpmt);
X printf("Enter month payments begin (ex: 8 = August): ");
X scanf("%f", &mbeg);
X
X /* compute payment and future value */
X
X r = rate/100.0;
X x = 1.0 + r/12.0;
X y = term*12.0;
X temp = (1.0 / pow(x,y));
X pmt = (amt*r/12.0) / (1-temp);
X k = term*12;
X fv = pmt*k;
X ic = fv - amt;
X
X printf("Do you want the report directed to a file or to the screen?");
X printf("\n[f = file / s = screen] : ");
X d = getchar(); /* This is only here to eat up the '\n' left over
X from the last scanf. */
X d = getchar();
X switch(d) {
X case 'f':
X d = getchar();
X printf("\nEnter a filename: ");
X scanf("%s", filename);
X while((c = getchar()) != '\n') {
X filename[a] = c; a++; }
X fp = fopen(filename, "w");
X break;
X default:
X fp = stdout;
X break;
X }
X
X /* print header */
X
X fprintf(fp,"\n\t\t *** Amortization Schedule ***\n\n");
X if (prpmt > 0) {
X fprintf(fp,"With no Additional Principal Payment your loan would be:\n");
X }
X fprintf(fp,"Ammount: %.2f\t", amt);
X fprintf(fp,"Rate: %.3f\t",rate);
X fprintf(fp,"Term: %.1f YRS\t", term);
X fprintf(fp,"Payment: %.2f\n", pmt);
X fprintf(fp,"Total cost of Loan: %.2f\t",fv);
X fprintf(fp,"Total Interest Paid: %.2f\n", ic);
X if (prpmt > 0) {
X fprintf(fp,"With an additional monthly Principal Payment of: %.2f",prpmt);
X }
X fprintf(fp,"\nYour payment schedule will be:\n");
X fprintf(fp,"\n\n ----------- Monthly -----------");
X fprintf(fp," --------- Accumulated ---------");
X fprintf(fp,"\nMONTH PRINCIPAL INTEREST BALANCE");
X fprintf(fp," PRINCIPAL INTEREST TOTAL\n");
X
X /* start of loop to print amortization schedule */
X
X mnbr=mbeg;
X for (i=1; amt > 0; i++) {
X month = i;
X exp = amt*(r/12.0);
X yrint=yrint+exp;
X prin = (pmt-exp)+prpmt;
X if (amt < pmt) {
X prin=amt;
X pmt=prin+exp;
X }
X amt = amt-prin;
X yrprin=yrprin+prin;
X acprin=acprin+prin;;
X acint=acint+exp;
X actotal=actotal+pmt;
X
X mnbr++;
X fprintf(fp,"%3d \t %10.2f %10.2f %10.2f %10.2f %10.2f %10.2f\n",
X month, prin, exp, amt, acprin, acint, actotal);
X
X if (mnbr > 12 ) {
X fprintf(fp,"\n \t %10.2f %10.2f = Total for Year %d\n\n",
X yrprin,yrint,yr);
X yr++;
X yrint=0;
X yrprin=0;
X
X mnbr=1;
X }
X}
Xif (mbeg > 1) {
X fprintf(fp,"\n \t %10.2f %10.2f = Total for Year %d\n\n",
X yrprin, yrint, yr);
X }
X fclose(fp);
X
X}
X/*-------end of file----------*/
*-*-END-of-mort.c-*-*
exit
--
John Sparks | {rutgers|uunet}!ukma!corpane!sparks | D.I.S.K. 24hrs 1200bps
||||||||||||||| sparks@corpane.UUCP | 502/968-5401 thru -5406
Chicken Little only has to be right once.