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c programming

Date: 2002/02/05 21:43

below is a very short program that is suppose to give a future value or an
equal payment amount. This is driving me bonkers. When I put in amounts
like 500, 1 and 12, I get crazy answers like 1.81e-301. What does this
mean? What am I doing wrong. Any help would be greatly appresiated I am
tearing out my hair!!!!

#include <stdio.h>
#include <math.h>
void main()
/* This program will calculate the future value or equal payment amounts

double present,future,equal,interest,periods;
int choice;

printf ("\n This program will calculate Future Value or Equal Payments.");
printf ("\n Enter a 1 for Future Value or a 2 for Equal Payments: ");
scanf ("%i", choice);

/* gather the user inputs */
printf ("\n\n Please enter the present value: ");
scanf ("%lg", present);
printf ("\n Please enter the Interest rate per period: ");
scanf ("%lg", interest);
printf ("\n Please enter the number of interest periods: ");
scanf ("%lg", periods);

if (choice = 1)
/* Calculate the Future Value */
future = present * ( pow(1 + interest,periods));

/* Display results */
printf ("\n\n The Future Value is %.4g",future);
/* subsection for calculating Equal Payments */
equal = present * (interest * pow(1 + interest,periods)) / pow(1 +
interest,periods) - 1;
/* Display results */
printf ("\n\n Equal Payment amount is %.4g",equal);
Nothing. That is really the result if your interest rate is 1200% (or you
have to divide the variable interest by 100 :-)


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