#include <math.h>
#include <iostream.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <conio.h>


double miles,f,a,q;

long last, i;

FILE *pFile[6];
char filename[6][15];


void main()
{
	   double pi=atan2(0.,-1.);


	   printf("\n\n Miles.cpp    ver 1.1    July 12, 2003");
	   printf("\n\n by Tom Irvine ");
   	   printf("\n Email: tomirvine@aol.com \n");
	   
	   printf("\n This program calculates the response of a single-degree-of-freedom "); 
	   printf("\n system to a base input power spectral density input via Miles equation. \n");
	   
       printf("\n\n Enter the natural frequency (Hz) \n");
	   scanf("\n %lf",&f);

       printf("\n\n Enter the PSD (G^2/Hz) value at the natural frequency \n");
	   scanf("\n %lf",&a);

       printf("\n\n Enter the Q value (typically Q=10) \n");
	   scanf("\n %lf",&q);


       miles=sqrt((pi/2.)*a*f*q);


	   printf("\n\n Acceleration Response = %10.2lf GRMS (1 sigma) ",miles);
	     printf("\n                       = %10.2lf G    (3 sigma) \n",3.*miles);

	   
       double om = 2.*pi*f;

	   double om2 = pow(om,2.);

       miles/=om2;

	   miles*=386.;

	   printf("\n\n Relative Displacement = %10.3g inch (1 sigma) ",miles);
	     printf("\n                       = %10.3g inch (3 sigma) \n",3.*miles);


       miles*=25.4;

	   printf("\n\n Relative Displacement = %10.3g mm (1 sigma) ",miles);
	     printf("\n                       = %10.3g mm (3 sigma) \n\n",3.*miles);


	   printf("\n\n Calculation complete. \n Press any key to exit.");
	   getch();
}